diff --git a/fusion_plating/CLAUDE.md b/fusion_plating/CLAUDE.md
index 03c1719b..59bdc5f8 100644
--- a/fusion_plating/CLAUDE.md
+++ b/fusion_plating/CLAUDE.md
@@ -370,7 +370,7 @@ rewrite code as new requirements surface. Each sub-project has its own design do
 | 2 | Part Data Model Overhaul (part#/rev required, dual descriptions, per-part cert requirement, SKU→Part Number on customer docs) | **Shipped 2026-04-22** (commits 868b418..afd8bae) | 2b, 2c, 2d, 4 |
 | 3 | Default Process + Composer per part (reuse recipe tree) | **Shipped 2026-04-22** (commits ce07daa..f059348) | 2e, 2f |
 | 4 | Contract Review (optional, per-part, settings-driven QA roster, QA-005 1:1 PDF) | **Shipped 2026-04-22** | 2i |
-| 5 | Order-line fields (serial, job#, thickness dropdown, revision picker) | Pending | 5, 6, Q2 |
+| 5 | Order-line fields (fp.serial registry, auto job#, coating-scoped thickness dropdown, revision picker) | **Shipped 2026-04-22** | 5, 6, Q2 |
 | 6 | Contact Profiles & Communication Routing (sub-contacts + per-location notification lists + global contacts) | Pending | client transcript A/B/C |
 | 7 | IoT tuning (configurable polling interval 15–30 min, seed 6–10 tank sensors) | Pending | client transcript D |
 | 8 | Receiving / Inspection / QC flow restructure (split receiving vs inspection; racking crew inspects, not receiver) | Pending | client transcript E |
diff --git a/fusion_plating/docs/superpowers/tests/2026-04-22-sub5-smoke.py b/fusion_plating/docs/superpowers/tests/2026-04-22-sub5-smoke.py
new file mode 100644
index 00000000..339c49c4
--- /dev/null
+++ b/fusion_plating/docs/superpowers/tests/2026-04-22-sub5-smoke.py
@@ -0,0 +1,149 @@
+"""Sub 5 smoke test — runs inside odoo-shell on entech."""
+env = env
+
+Partner = env['res.partner']
+Part = env['fp.part.catalog']
+Coating = env['fp.coating.config']
+Thickness = env['fp.coating.thickness']
+Serial = env['fp.serial']
+SO = env['sale.order']
+admin = env.ref('base.user_admin')
+
+# ---- Seed customer + part + coating + thickness options ---------------
+cust = Partner.create({
+    'name': 'Sub5 Smoke Customer',
+    'is_company': True,
+    'customer_rank': 1,
+})
+part_a = Part.create({
+    'partner_id': cust.id,
+    'part_number': 'SUB5-001',
+    'revision': 'A',
+})
+# Bump to a newer revision so we have A + B in the chain
+part_a.action_create_revision()
+part_b = Part.search([
+    ('parent_part_id', '=', (part_a.parent_part_id or part_a).id),
+    ('is_latest_revision', '=', True),
+], limit=1, order='revision_number desc')
+assert part_b.revision != part_a.revision, 'revision chain failed'
+print(f'[OK] Part revisions: A={part_a.revision} / latest={part_b.revision}')
+
+coating = Coating.search([], limit=1) or Coating.create({
+    'name': 'Sub5 Coating Test',
+    'process_type_id': env['fusion.plating.process.type'].search([], limit=1).id,
+})
+t1 = Thickness.create({
+    'coating_config_id': coating.id,
+    'value': 0.001, 'uom': 'inches', 'sequence': 10,
+})
+t2 = Thickness.create({
+    'coating_config_id': coating.id,
+    'value': 0.0015, 'uom': 'inches', 'sequence': 20,
+})
+print(f'[OK] Thickness options: {t1.display_name} / {t2.display_name}')
+
+# ---- Create SO with latest revision, assign serial via create-on-fly --
+product = env['product.product'].search([('sale_ok', '=', True)], limit=1)
+so = SO.create({
+    'partner_id': cust.id,
+    'x_fc_po_number': 'PO-SUB5-SMOKE',
+    'x_fc_po_received': True,
+    'order_line': [(0, 0, {
+        'product_id': product.id,
+        'product_uom_qty': 10,
+        'name': 'Sub5 smoke line',
+        'x_fc_part_catalog_id': part_b.id,
+        'x_fc_coating_config_id': coating.id,
+        'x_fc_thickness_id': t1.id,
+        'x_fc_internal_description': 'smoke',
+    })],
+})
+line = so.order_line[0]
+line.invalidate_recordset()
+assert line.x_fc_revision_snapshot == part_b.revision, (
+    f'snapshot mismatch: {line.x_fc_revision_snapshot} vs {part_b.revision}'
+)
+print(f'[OK] Revision snapshot captured on create: {line.x_fc_revision_snapshot}')
+
+# ---- Generate serial button -----------------------------------------
+line.action_generate_serial()
+line.invalidate_recordset()
+assert line.x_fc_serial_id, 'serial should be assigned'
+assert line.x_fc_serial_id.name.startswith('FP-SN-'), (
+    f'unexpected serial name: {line.x_fc_serial_id.name}'
+)
+print(f'[OK] Generate serial: {line.x_fc_serial_id.name}')
+
+# ---- Customer-typed serial --------------------------------------------
+so2 = SO.create({
+    'partner_id': cust.id,
+    'x_fc_po_number': 'PO-SUB5-SMOKE-2',
+    'x_fc_po_received': True,
+    'order_line': [(0, 0, {
+        'product_id': product.id,
+        'product_uom_qty': 5,
+        'name': 'Sub5 smoke line 2',
+        'x_fc_part_catalog_id': part_b.id,
+        'x_fc_coating_config_id': coating.id,
+        'x_fc_internal_description': 'smoke2',
+    })],
+})
+line2 = so2.order_line[0]
+typed_serial = Serial.create({'name': 'CUST-999'})
+line2.x_fc_serial_id = typed_serial.id
+line2.invalidate_recordset()
+assert line2.x_fc_serial_id.name == 'CUST-999'
+print('[OK] Customer-typed serial attached')
+
+# ---- Revision picker: switch to Rev A --------------------------------
+line.x_fc_revision_pick_id = part_a.id
+line.invalidate_recordset()
+assert line.x_fc_part_catalog_id == part_a, (
+    f'picker did not re-point part: {line.x_fc_part_catalog_id.revision}'
+)
+assert line.x_fc_revision_snapshot == part_a.revision
+print(f'[OK] Revision picker: switched to {part_a.revision}')
+
+# ---- Confirm SO → job number auto-assigned ---------------------------
+so.action_confirm()
+line.invalidate_recordset()
+assert line.x_fc_job_number, 'job number should be auto-assigned on confirm'
+assert line.x_fc_job_number.startswith('FP-JOB-'), (
+    f'unexpected job number: {line.x_fc_job_number}'
+)
+print(f'[OK] SO confirmed → job number: {line.x_fc_job_number}')
+
+# ---- MO carry-over (if bridge_mrp auto-created an MO) -----------------
+MO = env['mrp.production']
+mos = MO.search([('origin', '=', so.name)])
+if mos:
+    mo = mos[0]
+    print(f'[OK] MO created ({mo.name}) → serial={mo.x_fc_serial_id.name if mo.x_fc_serial_id else "—"} / job={mo.x_fc_job_number or "—"} / thickness={mo.x_fc_thickness_id.display_name if mo.x_fc_thickness_id else "—"} / rev={mo.x_fc_revision_snapshot or "—"}')
+    if mo.x_fc_serial_id:
+        assert mo.x_fc_serial_id == line.x_fc_serial_id, 'MO serial mismatch'
+        print('[OK] Serial carried MO ← SO line')
+else:
+    print('[SKIP] No MO auto-created for this SO')
+
+# ---- fp.serial smart-button counts reflect reality -------------------
+serial = line.x_fc_serial_id
+serial.invalidate_recordset()
+prod_cnt = serial.production_count
+del_cnt = serial.delivery_count
+print(f'[OK] Serial {serial.name}: MOs={prod_cnt}, Deliveries={del_cnt}, Invoices={serial.invoice_count}')
+
+# ---- Thickness dropdown domain ----------------------------------------
+another_coating = Coating.create({
+    'name': 'Sub5 Other Coating',
+    'process_type_id': coating.process_type_id.id,
+})
+line.x_fc_coating_config_id = another_coating.id
+line._onchange_coating_clears_thickness()
+line.invalidate_recordset()
+assert not line.x_fc_thickness_id, 'thickness should clear when coating changes'
+print('[OK] Thickness clears when coating switches')
+
+# ---- Cleanup ---------------------------------------------------------
+env.cr.rollback()
+print('\n=== SUB 5 SMOKE PASS — all assertions held ===')
diff --git a/fusion_plating/fusion_plating_bridge_mrp/__manifest__.py b/fusion_plating/fusion_plating_bridge_mrp/__manifest__.py
index a7bcf878..907dc1f7 100644
--- a/fusion_plating/fusion_plating_bridge_mrp/__manifest__.py
+++ b/fusion_plating/fusion_plating_bridge_mrp/__manifest__.py
@@ -5,7 +5,7 @@
 
 {
     "name": "Fusion Plating — MRP Bridge",
-    'version': '19.0.10.0.0',
+    'version': '19.0.11.0.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Bridge Fusion Plating facilities, baths and tanks to Odoo MRP work orders.',
     'description': """
@@ -74,6 +74,7 @@ Copyright (c) 2026 Nexa Systems Inc. All rights reserved.
         'views/fp_job_consumption_views.xml',
         'views/fp_work_role_views.xml',
         'views/res_partner_views.xml',
+        'views/fp_serial_views.xml',
     ],
     'assets': {
         'web.assets_backend': [
diff --git a/fusion_plating/fusion_plating_bridge_mrp/models/__init__.py b/fusion_plating/fusion_plating_bridge_mrp/models/__init__.py
index e535b3f1..ee70955b 100644
--- a/fusion_plating/fusion_plating_bridge_mrp/models/__init__.py
+++ b/fusion_plating/fusion_plating_bridge_mrp/models/__init__.py
@@ -23,3 +23,4 @@ from . import fp_qc_template
 from . import fp_quality_check
 from . import fp_thickness_reading
 from . import res_partner
+from . import fp_serial
diff --git a/fusion_plating/fusion_plating_bridge_mrp/models/fp_serial.py b/fusion_plating/fusion_plating_bridge_mrp/models/fp_serial.py
new file mode 100644
index 00000000..737c17f1
--- /dev/null
+++ b/fusion_plating/fusion_plating_bridge_mrp/models/fp_serial.py
@@ -0,0 +1,26 @@
+# -*- coding: utf-8 -*-
+# Copyright 2026 Nexa Systems Inc.
+# License OPL-1 (Odoo Proprietary License v1.0)
+# Part of the Fusion Plating product family.
+#
+# Sub 5 — attach MO reverse links to fp.serial. Defined here rather than
+# in fusion_plating_configurator because configurator loads before
+# bridge_mrp; declaring the O2M at configurator setup time would fail
+# because mrp.production.x_fc_serial_id wouldn't exist yet.
+
+from odoo import api, fields, models
+
+
+class FpSerial(models.Model):
+    _inherit = 'fp.serial'
+
+    production_ids = fields.One2many(
+        'mrp.production', 'x_fc_serial_id',
+        string='Manufacturing Orders',
+    )
+    production_count = fields.Integer(compute='_compute_production_count')
+
+    @api.depends('production_ids')
+    def _compute_production_count(self):
+        for rec in self:
+            rec.production_count = len(rec.production_ids)
diff --git a/fusion_plating/fusion_plating_bridge_mrp/models/mrp_production.py b/fusion_plating/fusion_plating_bridge_mrp/models/mrp_production.py
index 0c9c13ae..1a5ab2ce 100644
--- a/fusion_plating/fusion_plating_bridge_mrp/models/mrp_production.py
+++ b/fusion_plating/fusion_plating_bridge_mrp/models/mrp_production.py
@@ -111,6 +111,29 @@ class MrpProduction(models.Model):
              'before this one. Copied from the first SO line that set it.',
     )
 
+    # ---- Sub 5 — traceability fields copied from the source SO line --------
+    # Populated by bridge_mrp's _prepare_mo_vals override, which pulls these
+    # from the first linked SO line. Lets the fp.serial registry show every
+    # MO it spawned via a direct FK rather than heuristic origin matching.
+    x_fc_serial_id = fields.Many2one(
+        'fp.serial', string='Serial Number',
+        ondelete='set null', index=True,
+        help='Serial number from the source SO line.',
+    )
+    x_fc_job_number = fields.Char(
+        string='Job #', index=True,
+        help='Shop-floor job number from the source SO line.',
+    )
+    x_fc_thickness_id = fields.Many2one(
+        'fp.coating.thickness', string='Thickness',
+        ondelete='set null',
+        help='Target coating thickness from the source SO line. Prints on the traveller.',
+    )
+    x_fc_revision_snapshot = fields.Char(
+        string='Revision (snapshot)',
+        help='Revision letter captured on the source SO line at save time.',
+    )
+
     # ------------------------------------------------------------------
     # T1.4 — Rework / strip-and-replate
     # ------------------------------------------------------------------
@@ -1287,7 +1310,7 @@ class MrpProduction(models.Model):
                 ('active', '=', True),
             ], order='id', limit=1)
 
-        return {
+        vals = {
             'company_id': mo.company_id.id or self.env.company.id,
             'partner_id': job.partner_id.id,
             'job_ref': job.name,
@@ -1298,6 +1321,20 @@ class MrpProduction(models.Model):
             'assigned_driver_id': driver.id if driver else False,
             'state': 'draft',
         }
+        # Sub 5 — carry serial / job# / thickness / revision from the MO
+        # onto the draft delivery for end-to-end traceability.
+        Delivery = self.env.get('fusion.plating.delivery')
+        if Delivery is not None:
+            for fname in ('x_fc_serial_id', 'x_fc_job_number',
+                          'x_fc_thickness_id', 'x_fc_revision_snapshot'):
+                if fname in Delivery._fields and fname in mo._fields:
+                    value = mo[fname]
+                    if value:
+                        if hasattr(value, 'id'):
+                            vals[fname] = value.id
+                        else:
+                            vals[fname] = value
+        return vals
 
     # ------------------------------------------------------------------
     # #3 — Render the cert PDF + cross-link it everywhere it's needed
diff --git a/fusion_plating/fusion_plating_bridge_mrp/models/sale_order.py b/fusion_plating/fusion_plating_bridge_mrp/models/sale_order.py
index b1844bad..294143b2 100644
--- a/fusion_plating/fusion_plating_bridge_mrp/models/sale_order.py
+++ b/fusion_plating/fusion_plating_bridge_mrp/models/sale_order.py
@@ -212,6 +212,13 @@ class SaleOrder(models.Model):
                         start_node = ln.x_fc_start_at_node_id
                         break
 
+                # Sub 5 — carry serial / job# / thickness / revision from
+                # the first line of the group. Single-line groups pick it up
+                # cleanly; multi-line groups inherit the primary line's
+                # tracking data. These fields are metadata only (reports and
+                # smart buttons), so a "first line wins" rule is safe.
+                primary = lines[0]
+
                 mo_vals = {
                     'product_id': product.id,
                     'product_qty': qty,
@@ -224,6 +231,14 @@ class SaleOrder(models.Model):
                     mo_vals['x_fc_recipe_id'] = recipe.id
                 if start_node:
                     mo_vals['x_fc_start_at_node_id'] = start_node.id
+                if 'x_fc_serial_id' in Production._fields and primary.x_fc_serial_id:
+                    mo_vals['x_fc_serial_id'] = primary.x_fc_serial_id.id
+                if 'x_fc_job_number' in Production._fields and primary.x_fc_job_number:
+                    mo_vals['x_fc_job_number'] = primary.x_fc_job_number
+                if 'x_fc_thickness_id' in Production._fields and primary.x_fc_thickness_id:
+                    mo_vals['x_fc_thickness_id'] = primary.x_fc_thickness_id.id
+                if 'x_fc_revision_snapshot' in Production._fields and primary.x_fc_revision_snapshot:
+                    mo_vals['x_fc_revision_snapshot'] = primary.x_fc_revision_snapshot
                 mo = Production.create(mo_vals)
                 created.append((mo, tag, len(lines)))
                 self.env.cr.execute('RELEASE SAVEPOINT %s' % savepoint_name)
diff --git a/fusion_plating/fusion_plating_bridge_mrp/views/fp_serial_views.xml b/fusion_plating/fusion_plating_bridge_mrp/views/fp_serial_views.xml
new file mode 100644
index 00000000..af4bc5cb
--- /dev/null
+++ b/fusion_plating/fusion_plating_bridge_mrp/views/fp_serial_views.xml
@@ -0,0 +1,122 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Copyright 2026 Nexa Systems Inc.
+    License OPL-1 (Odoo Proprietary License v1.0)
+    Part of the Fusion Plating product family.
+    Sub 5 — Serial Number registry views.
+-->
+<odoo>
+
+    <record id="view_fp_serial_form" model="ir.ui.view">
+        <field name="name">fp.serial.form</field>
+        <field name="model">fp.serial</field>
+        <field name="arch" type="xml">
+            <form string="Serial Number">
+                <sheet>
+                    <div class="oe_button_box" name="button_box">
+                        <button name="action_view_sale_order" type="object"
+                                class="oe_stat_button" icon="fa-file-text-o"
+                                invisible="not sale_order_id">
+                            <div class="o_stat_info">
+                                <span class="o_stat_text">Sale Order</span>
+                            </div>
+                        </button>
+                        <button name="action_view_productions" type="object"
+                                class="oe_stat_button" icon="fa-cogs"
+                                invisible="production_count == 0">
+                            <field name="production_count" widget="statinfo" string="MOs"/>
+                        </button>
+                        <button name="action_view_deliveries" type="object"
+                                class="oe_stat_button" icon="fa-truck"
+                                invisible="delivery_count == 0">
+                            <field name="delivery_count" widget="statinfo" string="Deliveries"/>
+                        </button>
+                        <button name="action_view_invoices" type="object"
+                                class="oe_stat_button" icon="fa-money"
+                                invisible="invoice_count == 0">
+                            <field name="invoice_count" widget="statinfo" string="Invoices"/>
+                        </button>
+                        <button name="action_view_part" type="object"
+                                class="oe_stat_button" icon="fa-cube"
+                                invisible="not part_id">
+                            <div class="o_stat_info">
+                                <span class="o_stat_text">Part</span>
+                            </div>
+                        </button>
+                    </div>
+                    <div class="oe_title">
+                        <label for="name" string="Serial #"/>
+                        <h1><field name="name" placeholder="e.g. SN-12345"/></h1>
+                    </div>
+                    <group>
+                        <group>
+                            <field name="customer_id" readonly="1"/>
+                            <field name="part_id" readonly="1"/>
+                            <field name="sale_order_id" readonly="1"/>
+                        </group>
+                        <group>
+                            <field name="sale_order_line_id" readonly="1"/>
+                            <field name="company_id" groups="base.group_multi_company"/>
+                        </group>
+                    </group>
+                    <notebook>
+                        <page string="Notes" name="notes">
+                            <field name="notes" nolabel="1"/>
+                        </page>
+                    </notebook>
+                </sheet>
+                <chatter/>
+            </form>
+        </field>
+    </record>
+
+    <record id="view_fp_serial_list" model="ir.ui.view">
+        <field name="name">fp.serial.list</field>
+        <field name="model">fp.serial</field>
+        <field name="arch" type="xml">
+            <list string="Serial Numbers">
+                <field name="name"/>
+                <field name="customer_id"/>
+                <field name="part_id"/>
+                <field name="sale_order_id"/>
+                <field name="production_count" string="MOs"/>
+                <field name="delivery_count" string="Deliveries"/>
+                <field name="invoice_count" string="Invoices"/>
+                <field name="create_date"/>
+            </list>
+        </field>
+    </record>
+
+    <record id="view_fp_serial_search" model="ir.ui.view">
+        <field name="name">fp.serial.search</field>
+        <field name="model">fp.serial</field>
+        <field name="arch" type="xml">
+            <search>
+                <field name="name"/>
+                <field name="customer_id"/>
+                <field name="part_id"/>
+                <field name="sale_order_id"/>
+                <group>
+                    <filter name="group_customer" string="Customer"
+                            context="{'group_by': 'customer_id'}"/>
+                    <filter name="group_part" string="Part"
+                            context="{'group_by': 'part_id'}"/>
+                </group>
+            </search>
+        </field>
+    </record>
+
+    <record id="action_fp_serial" model="ir.actions.act_window">
+        <field name="name">Serial Numbers</field>
+        <field name="res_model">fp.serial</field>
+        <field name="view_mode">list,form</field>
+        <field name="search_view_id" ref="view_fp_serial_search"/>
+    </record>
+
+    <menuitem id="menu_fp_serial"
+              name="Serial Numbers"
+              parent="fusion_plating_configurator.menu_fp_sales"
+              action="action_fp_serial"
+              sequence="60"/>
+
+</odoo>
diff --git a/fusion_plating/fusion_plating_configurator/__manifest__.py b/fusion_plating/fusion_plating_configurator/__manifest__.py
index e3dba900..6054895e 100644
--- a/fusion_plating/fusion_plating_configurator/__manifest__.py
+++ b/fusion_plating/fusion_plating_configurator/__manifest__.py
@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — Configurator',
-    'version': '19.0.11.0.0',
+    'version': '19.0.12.0.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Quotation configurator with part catalog, coating configs, and formula-based pricing engine.',
     'description': """
@@ -38,6 +38,7 @@ Provides:
         'security/fp_configurator_security.xml',
         'security/ir.model.access.csv',
         'data/fp_configurator_sequence_data.xml',
+        'data/fp_sub5_sequence_data.xml',
         'data/fp_treatment_data.xml',
         'views/fp_treatment_views.xml',
         'views/fp_part_catalog_views.xml',
diff --git a/fusion_plating/fusion_plating_configurator/data/fp_sub5_sequence_data.xml b/fusion_plating/fusion_plating_configurator/data/fp_sub5_sequence_data.xml
new file mode 100644
index 00000000..5aee6f20
--- /dev/null
+++ b/fusion_plating/fusion_plating_configurator/data/fp_sub5_sequence_data.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Copyright 2026 Nexa Systems Inc.
+    License OPL-1 (Odoo Proprietary License v1.0)
+    Part of the Fusion Plating product family.
+    Sub 5 — sequences for serial numbers and job numbers on SO lines.
+-->
+<odoo noupdate="1">
+
+    <record id="seq_fp_serial" model="ir.sequence">
+        <field name="name">Fusion Plating: Serial Number</field>
+        <field name="code">fp.serial</field>
+        <field name="prefix">FP-SN-</field>
+        <field name="padding">5</field>
+        <field name="company_id" eval="False"/>
+    </record>
+
+    <record id="seq_fp_job_number" model="ir.sequence">
+        <field name="name">Fusion Plating: Job Number</field>
+        <field name="code">fp.job.number</field>
+        <field name="prefix">FP-JOB-</field>
+        <field name="padding">5</field>
+        <field name="company_id" eval="False"/>
+    </record>
+
+</odoo>
diff --git a/fusion_plating/fusion_plating_configurator/models/__init__.py b/fusion_plating/fusion_plating_configurator/models/__init__.py
index 25c2ab94..5e21cc87 100644
--- a/fusion_plating/fusion_plating_configurator/models/__init__.py
+++ b/fusion_plating/fusion_plating_configurator/models/__init__.py
@@ -5,12 +5,14 @@
 
 from . import fp_treatment
 from . import fp_part_catalog
+from . import fp_coating_thickness
 from . import fp_coating_config
 from . import fp_pricing_complexity_surcharge
 from . import fp_pricing_rule
 from . import fp_customer_price_list
 from . import fp_sale_description_template
 from . import fp_quote_configurator
+from . import fp_serial
 from . import sale_order
 from . import sale_order_line
 from . import account_move_line
diff --git a/fusion_plating/fusion_plating_configurator/models/account_move_line.py b/fusion_plating/fusion_plating_configurator/models/account_move_line.py
index 6f4ebda0..6c154128 100644
--- a/fusion_plating/fusion_plating_configurator/models/account_move_line.py
+++ b/fusion_plating/fusion_plating_configurator/models/account_move_line.py
@@ -19,3 +19,23 @@ class AccountMoveLine(models.Model):
         help="Copied from sale.order.line on invoice creation so customer-"
              "facing invoice PDFs can render the customer's part number.",
     )
+    # ---- Sub 5 ---------------------------------------------------------------
+    x_fc_serial_id = fields.Many2one(
+        'fp.serial',
+        string='Serial Number',
+        index=True,
+        help='Copied from sale.order.line for traceability.',
+    )
+    x_fc_job_number = fields.Char(
+        string='Job #', index=True,
+        help='Copied from sale.order.line.',
+    )
+    x_fc_thickness_id = fields.Many2one(
+        'fp.coating.thickness',
+        string='Thickness',
+        help='Copied from sale.order.line for customer-facing invoice PDFs.',
+    )
+    x_fc_revision_snapshot = fields.Char(
+        string='Revision (snapshot)',
+        help='Revision letter from the source SO line.',
+    )
diff --git a/fusion_plating/fusion_plating_configurator/models/fp_coating_config.py b/fusion_plating/fusion_plating_configurator/models/fp_coating_config.py
index d5b287f4..ef798622 100644
--- a/fusion_plating/fusion_plating_configurator/models/fp_coating_config.py
+++ b/fusion_plating/fusion_plating_configurator/models/fp_coating_config.py
@@ -37,6 +37,14 @@ class FpCoatingConfig(models.Model):
         [('mils', 'mils'), ('microns', 'microns'), ('inches', 'inches')],
         string='Thickness UoM', default='mils',
     )
+    thickness_option_ids = fields.One2many(
+        'fp.coating.thickness',
+        'coating_config_id',
+        string='Thickness Options',
+        help='Discrete thickness values the estimator can pick from when '
+             'this coating appears on a sale order line. Each value is '
+             'driven by the spec the coating is built against. Sub 5.',
+    )
     spec_reference = fields.Char(string='Spec Reference', help='e.g. "AMS 2404", "E499-303-00-005"')
     certification_level = fields.Selection(
         [('commercial', 'Commercial'), ('mil_spec', 'Mil-Spec'),
diff --git a/fusion_plating/fusion_plating_configurator/models/fp_coating_thickness.py b/fusion_plating/fusion_plating_configurator/models/fp_coating_thickness.py
new file mode 100644
index 00000000..94a762bf
--- /dev/null
+++ b/fusion_plating/fusion_plating_configurator/models/fp_coating_thickness.py
@@ -0,0 +1,58 @@
+# -*- coding: utf-8 -*-
+# Copyright 2026 Nexa Systems Inc.
+# License OPL-1 (Odoo Proprietary License v1.0)
+# Part of the Fusion Plating product family.
+
+from odoo import _, api, fields, models
+
+
+class FpCoatingThickness(models.Model):
+    """Allowed thickness option for a coating configuration.
+
+    Each plating process (ENP Class 4, hard chrome 0.001", Type III
+    anodize, etc.) has its own set of valid thicknesses driven by the
+    spec it's built from. This child of `fp.coating.config` holds the
+    discrete options so the SO-line thickness dropdown can filter to
+    only what's actually achievable for the line's coating.
+    """
+    _name = 'fp.coating.thickness'
+    _description = 'Coating Thickness Option'
+    _order = 'coating_config_id, sequence, value'
+
+    coating_config_id = fields.Many2one(
+        'fp.coating.config',
+        required=True,
+        ondelete='cascade',
+    )
+    value = fields.Float(
+        digits=(10, 4),
+        required=True,
+        help='Target thickness value (magnitude only; UoM in the next field).',
+    )
+    uom = fields.Selection(
+        [('mils', 'mils (0.001 in)'),
+         ('microns', 'microns (µm)'),
+         ('inches', 'inches'),
+         ('mm', 'mm')],
+        required=True,
+        default='mils',
+    )
+    sequence = fields.Integer(default=10)
+    active = fields.Boolean(default=True)
+    display_name = fields.Char(
+        compute='_compute_display_name',
+        store=True,
+    )
+
+    @api.depends('value', 'uom')
+    def _compute_display_name(self):
+        uom_labels = dict(self._fields['uom'].selection)
+        for rec in self:
+            label = uom_labels.get(rec.uom, rec.uom or '')
+            # Strip the bracketed clarification for a tighter dropdown row.
+            if ' (' in label:
+                label = label.split(' (')[0]
+            if rec.value:
+                rec.display_name = f'{rec.value:g} {label}'.strip()
+            else:
+                rec.display_name = label
diff --git a/fusion_plating/fusion_plating_configurator/models/fp_serial.py b/fusion_plating/fusion_plating_configurator/models/fp_serial.py
new file mode 100644
index 00000000..24476945
--- /dev/null
+++ b/fusion_plating/fusion_plating_configurator/models/fp_serial.py
@@ -0,0 +1,151 @@
+# -*- coding: utf-8 -*-
+# Copyright 2026 Nexa Systems Inc.
+# License OPL-1 (Odoo Proprietary License v1.0)
+# Part of the Fusion Plating product family.
+
+from odoo import _, api, fields, models
+
+
+class FpSerial(models.Model):
+    """Serial number registry.
+
+    One record per "occurrence of a part on an order line". The same part
+    ordered six months later gets a different serial. The serial is the
+    common thread linking the SO line to the MO, Delivery, and Invoice
+    records it spawns downstream.
+
+    Most serials are customer-supplied (pass-through from the customer's
+    own end-user); a smaller share are shop-generated via the sequence.
+    The registry is optional — SO lines can carry no serial at all.
+    """
+    _name = 'fp.serial'
+    _description = 'Fusion Plating — Serial Number'
+    _inherit = ['mail.thread', 'mail.activity.mixin']
+    _order = 'create_date desc, id desc'
+    _rec_name = 'name'
+
+    name = fields.Char(
+        required=True,
+        tracking=True,
+        help='Customer-supplied serial (most common) or shop-generated '
+             'sequence value. Typed-in values are accepted as-is.',
+    )
+    company_id = fields.Many2one(
+        'res.company', required=True,
+        default=lambda s: s.env.company,
+    )
+    sale_order_line_id = fields.Many2one(
+        'sale.order.line',
+        string='Source Sale Order Line',
+        ondelete='set null',
+        copy=False,
+        tracking=True,
+    )
+    sale_order_id = fields.Many2one(
+        related='sale_order_line_id.order_id',
+        store=True,
+        string='Sale Order',
+    )
+    customer_id = fields.Many2one(
+        related='sale_order_line_id.order_id.partner_id',
+        store=True,
+        string='Customer',
+    )
+    part_id = fields.Many2one(
+        related='sale_order_line_id.x_fc_part_catalog_id',
+        store=True,
+        string='Part',
+    )
+    notes = fields.Text(string='Notes')
+
+    # Reverse link to invoice lines — safe here because account.move.line
+    # lives in this same module. Production (mrp) and delivery (logistics)
+    # reverse links are defined in their own modules' fp_serial inherits
+    # to keep module load order consistent.
+    invoice_line_ids = fields.One2many(
+        'account.move.line', 'x_fc_serial_id',
+        string='Invoice Lines',
+    )
+    invoice_ids = fields.Many2many(
+        'account.move',
+        compute='_compute_invoice_ids',
+        string='Invoices',
+    )
+
+    invoice_count = fields.Integer(compute='_compute_counts')
+    # production_count / delivery_count are declared in the inheriting
+    # modules (bridge_mrp / logistics) so the O2Ms exist alongside them.
+
+    _sql_constraints = [
+        ('fp_serial_name_company_uniq',
+         'unique(company_id, name)',
+         'Serial number must be unique within the company.'),
+    ]
+
+    # ---- Computes ------------------------------------------------------------
+
+    @api.depends('invoice_line_ids.move_id')
+    def _compute_counts(self):
+        # Base compute sets invoice_count only. bridge_mrp + logistics
+        # override this to also populate production_count / delivery_count.
+        for rec in self:
+            rec.invoice_count = len(rec.invoice_line_ids.mapped('move_id'))
+
+    @api.depends('invoice_line_ids.move_id')
+    def _compute_invoice_ids(self):
+        for rec in self:
+            rec.invoice_ids = rec.invoice_line_ids.mapped('move_id')
+
+    # ---- Actions -------------------------------------------------------------
+
+    def action_view_sale_order(self):
+        self.ensure_one()
+        if not self.sale_order_id:
+            return False
+        return {
+            'type': 'ir.actions.act_window',
+            'res_model': 'sale.order',
+            'res_id': self.sale_order_id.id,
+            'view_mode': 'form',
+        }
+
+    def action_view_productions(self):
+        self.ensure_one()
+        return {
+            'type': 'ir.actions.act_window',
+            'name': _('Manufacturing Orders'),
+            'res_model': 'mrp.production',
+            'domain': [('id', 'in', self.production_ids.ids)],
+            'view_mode': 'list,form',
+        }
+
+    def action_view_deliveries(self):
+        self.ensure_one()
+        return {
+            'type': 'ir.actions.act_window',
+            'name': _('Deliveries'),
+            'res_model': 'fusion.plating.delivery',
+            'domain': [('id', 'in', self.delivery_ids.ids)],
+            'view_mode': 'list,form',
+        }
+
+    def action_view_invoices(self):
+        self.ensure_one()
+        return {
+            'type': 'ir.actions.act_window',
+            'name': _('Invoices'),
+            'res_model': 'account.move',
+            'domain': [('id', 'in', self.invoice_ids.ids)],
+            'view_mode': 'list,form',
+        }
+
+    def action_view_part(self):
+        self.ensure_one()
+        if not self.part_id:
+            return False
+        return {
+            'type': 'ir.actions.act_window',
+            'res_model': 'fp.part.catalog',
+            'res_id': self.part_id.id,
+            'view_mode': 'form',
+        }
diff --git a/fusion_plating/fusion_plating_configurator/models/sale_order.py b/fusion_plating/fusion_plating_configurator/models/sale_order.py
index 1f620ef9..012b9e18 100644
--- a/fusion_plating/fusion_plating_configurator/models/sale_order.py
+++ b/fusion_plating/fusion_plating_configurator/models/sale_order.py
@@ -579,3 +579,20 @@ class SaleOrder(models.Model):
                 'title': 'PO — %s' % (self.x_fc_po_attachment_id.name or ''),
             },
         }
+
+    # ---- Sub 5 — auto-assign Job # on confirm -------------------------------
+    # Job # is the shop-floor reference that prints on travellers and WOs.
+    # Auto-assigned once at confirm so every confirmed line has one; still
+    # editable afterwards (clearable, overridable to match a customer scheme).
+    def action_confirm(self):
+        res = super().action_confirm()
+        Sequence = self.env['ir.sequence']
+        for so in self:
+            for line in so.order_line:
+                if line.display_type:
+                    continue
+                if not line.x_fc_job_number:
+                    line.x_fc_job_number = Sequence.next_by_code(
+                        'fp.job.number'
+                    ) or False
+        return res
diff --git a/fusion_plating/fusion_plating_configurator/models/sale_order_line.py b/fusion_plating/fusion_plating_configurator/models/sale_order_line.py
index 121d8b40..8e8dad98 100644
--- a/fusion_plating/fusion_plating_configurator/models/sale_order_line.py
+++ b/fusion_plating/fusion_plating_configurator/models/sale_order_line.py
@@ -67,6 +67,66 @@ class SaleOrderLine(models.Model):
              'preserved for audit. Useful when a part is cancelled mid-order.',
     )
 
+    # ---- Sub 5 — Order-line fields (serial / job# / thickness / revision) ---
+    # NB: sale.order.line in Odoo 19 does not support `tracking=True` on
+    # inherited fields — Odoo emits a warning and ignores it. Audit trail
+    # for these values lives on fp.serial.mail.thread instead.
+    x_fc_serial_id = fields.Many2one(
+        'fp.serial',
+        string='Serial Number',
+        ondelete='set null',
+        copy=False,
+        help='Customer-supplied serial number for this line. Optional. '
+             'Typing a value offers to create a new fp.serial record on '
+             'the fly; use the Generate Serial button to auto-sequence.',
+    )
+    x_fc_job_number = fields.Char(
+        string='Job #',
+        copy=False,
+        index=True,
+        help='Shop-floor reference for this line. Auto-sequenced on sale '
+             'order confirmation; editable. Blank is allowed.',
+    )
+    x_fc_thickness_id = fields.Many2one(
+        'fp.coating.thickness',
+        string='Thickness',
+        ondelete='set null',
+        domain="[('coating_config_id', '=', x_fc_coating_config_id)]",
+        help="Target coating thickness. Options come from the line's "
+             'coating configuration.',
+    )
+    x_fc_revision_snapshot = fields.Char(
+        string='Revision (snapshot)',
+        copy=False,
+        readonly=True,
+        help='Revision letter / number at the moment the line was saved. '
+             'Preserved even if the part catalog revision is later edited '
+             'or the catalog row is removed.',
+    )
+
+    # Revision picker — non-stored compute that re-points x_fc_part_catalog_id
+    # to any revision of the same part number. The Part M2O itself is domain-
+    # filtered to latest revisions only, so the picker is what surfaces
+    # earlier revisions when the estimator needs one.
+    x_fc_revision_pick_id = fields.Many2one(
+        'fp.part.catalog',
+        string='Revision',
+        compute='_compute_revision_pick_id',
+        inverse='_inverse_revision_pick_id',
+        store=False,
+        help='Switch to a different revision of the same part number.',
+    )
+
+    @api.depends('x_fc_part_catalog_id')
+    def _compute_revision_pick_id(self):
+        for line in self:
+            line.x_fc_revision_pick_id = line.x_fc_part_catalog_id
+
+    def _inverse_revision_pick_id(self):
+        for line in self:
+            if line.x_fc_revision_pick_id:
+                line.x_fc_part_catalog_id = line.x_fc_revision_pick_id
+
     @api.model_create_multi
     def create(self, vals_list):
         """Default `x_fc_internal_description` from `name` when a caller
@@ -82,21 +142,43 @@ class SaleOrderLine(models.Model):
         back-filled historical lines.
         """
         Product = self.env['product.product']
+        Part = self.env['fp.part.catalog']
         for vals in vals_list:
-            if vals.get('x_fc_internal_description'):
-                continue
-            # Try the explicit `name` first. If the caller didn't pass
-            # one (sale_mrp + some Odoo internals don't — they let the
-            # name compute from product_id later), fall back to the
-            # product's display_name so we have SOMETHING non-empty.
-            fallback = vals.get('name')
-            if not fallback and vals.get('product_id'):
-                prod = Product.browse(vals['product_id']).exists()
-                if prod:
-                    fallback = prod.display_name or prod.name
-            vals['x_fc_internal_description'] = fallback or '—'
+            if not vals.get('x_fc_internal_description'):
+                # Try the explicit `name` first. If the caller didn't pass
+                # one (sale_mrp + some Odoo internals don't — they let the
+                # name compute from product_id later), fall back to the
+                # product's display_name so we have SOMETHING non-empty.
+                fallback = vals.get('name')
+                if not fallback and vals.get('product_id'):
+                    prod = Product.browse(vals['product_id']).exists()
+                    if prod:
+                        fallback = prod.display_name or prod.name
+                vals['x_fc_internal_description'] = fallback or '—'
+
+            # Sub 5 — freeze the revision letter on the line at save time.
+            # Protects historical SOs from later edits to the catalog row.
+            if not vals.get('x_fc_revision_snapshot') and vals.get('x_fc_part_catalog_id'):
+                part = Part.browse(vals['x_fc_part_catalog_id']).exists()
+                if part and part.revision:
+                    vals['x_fc_revision_snapshot'] = part.revision
         return super().create(vals_list)
 
+    def write(self, vals):
+        # Sub 5 — keep the revision snapshot in lockstep with the line's
+        # part catalog pointer. Only refresh when the part changes; never
+        # overwrite a snapshot that's already been set on a historical line.
+        if 'x_fc_part_catalog_id' in vals:
+            Part = self.env['fp.part.catalog']
+            new_part = Part.browse(vals['x_fc_part_catalog_id']).exists()
+            if new_part and new_part.revision:
+                vals.setdefault('x_fc_revision_snapshot', new_part.revision)
+                # Blank overrides keep their snapshot; explicit changes do too.
+                for line in self:
+                    if line.x_fc_part_catalog_id.id != new_part.id:
+                        line.x_fc_revision_snapshot = new_part.revision
+        return super().write(vals)
+
     @api.onchange('x_fc_description_template_id')
     def _onchange_description_template(self):
         """When estimator picks a template, auto-fill both descriptions.
@@ -122,13 +204,55 @@ class SaleOrderLine(models.Model):
         return True
 
     def _prepare_invoice_line(self, **optional_values):
-        """Carry x_fc_part_catalog_id from SO line to invoice line.
+        """Carry x_fc_part_catalog_id + Sub 5 fields from SO line to invoice line.
 
         Sub 2 Task 19 — lets the customer-facing invoice PDF render the
         customer's part number via the shared customer_line_header macro
         instead of the internal service SKU.
+
+        Sub 5 — also carry serial / job# / thickness / revision snapshot so
+        the same macro can print them unchanged on invoices.
         """
         vals = super()._prepare_invoice_line(**optional_values)
         if self.x_fc_part_catalog_id:
             vals['x_fc_part_catalog_id'] = self.x_fc_part_catalog_id.id
+        if self.x_fc_serial_id:
+            vals['x_fc_serial_id'] = self.x_fc_serial_id.id
+        if self.x_fc_job_number:
+            vals['x_fc_job_number'] = self.x_fc_job_number
+        if self.x_fc_thickness_id:
+            vals['x_fc_thickness_id'] = self.x_fc_thickness_id.id
+        if self.x_fc_revision_snapshot:
+            vals['x_fc_revision_snapshot'] = self.x_fc_revision_snapshot
         return vals
+
+    @api.onchange('x_fc_coating_config_id')
+    def _onchange_coating_clears_thickness(self):
+        """Clear the thickness picker when coating config changes.
+
+        The thickness options are scoped to the coating config; a value
+        carried over from a previous coating would fail its domain.
+        """
+        for line in self:
+            if (line.x_fc_thickness_id
+                    and line.x_fc_thickness_id.coating_config_id
+                    != line.x_fc_coating_config_id):
+                line.x_fc_thickness_id = False
+
+    def action_generate_serial(self):
+        """Create a fresh fp.serial for this line using the shop sequence."""
+        self.ensure_one()
+        if self.x_fc_serial_id:
+            return {
+                'type': 'ir.actions.act_window',
+                'res_model': 'fp.serial',
+                'res_id': self.x_fc_serial_id.id,
+                'view_mode': 'form',
+            }
+        seq = self.env['ir.sequence'].next_by_code('fp.serial') or 'FP-SN-0000'
+        serial = self.env['fp.serial'].create({
+            'name': seq,
+            'sale_order_line_id': self.id,
+        })
+        self.x_fc_serial_id = serial.id
+        return False
diff --git a/fusion_plating/fusion_plating_configurator/security/ir.model.access.csv b/fusion_plating/fusion_plating_configurator/security/ir.model.access.csv
index a49ee5f5..262997aa 100644
--- a/fusion_plating/fusion_plating_configurator/security/ir.model.access.csv
+++ b/fusion_plating/fusion_plating_configurator/security/ir.model.access.csv
@@ -39,3 +39,9 @@ access_fp_customer_price_list_manager,fp.customer.price.list.manager,model_fp_cu
 access_fp_sale_desc_template_user,fp.sale.description.template.user,model_fp_sale_description_template,base.group_user,1,0,0,0
 access_fp_sale_desc_template_estimator,fp.sale.description.template.estimator,model_fp_sale_description_template,fusion_plating_configurator.group_fp_estimator,1,1,1,0
 access_fp_sale_desc_template_manager,fp.sale.description.template.manager,model_fp_sale_description_template,fusion_plating.group_fusion_plating_manager,1,1,1,1
+access_fp_serial_user,fp.serial.user,model_fp_serial,base.group_user,1,0,0,0
+access_fp_serial_estimator,fp.serial.estimator,model_fp_serial,fusion_plating_configurator.group_fp_estimator,1,1,1,0
+access_fp_serial_manager,fp.serial.manager,model_fp_serial,fusion_plating.group_fusion_plating_manager,1,1,1,1
+access_fp_coating_thickness_user,fp.coating.thickness.user,model_fp_coating_thickness,base.group_user,1,0,0,0
+access_fp_coating_thickness_estimator,fp.coating.thickness.estimator,model_fp_coating_thickness,fusion_plating_configurator.group_fp_estimator,1,1,1,0
+access_fp_coating_thickness_manager,fp.coating.thickness.manager,model_fp_coating_thickness,fusion_plating.group_fusion_plating_manager,1,1,1,1
diff --git a/fusion_plating/fusion_plating_configurator/views/fp_coating_config_views.xml b/fusion_plating/fusion_plating_configurator/views/fp_coating_config_views.xml
index 83b44714..763bc8ff 100644
--- a/fusion_plating/fusion_plating_configurator/views/fp_coating_config_views.xml
+++ b/fusion_plating/fusion_plating_configurator/views/fp_coating_config_views.xml
@@ -66,6 +66,24 @@
                         <page string="Description" name="description">
                             <field name="description" placeholder="Detailed description of this coating configuration..."/>
                         </page>
+                        <page string="Thickness Options" name="thickness_options">
+                            <p class="text-muted">
+                                Discrete thickness values the estimator can pick when
+                                this coating appears on a sale order line. Each value
+                                is driven by the spec this coating is built against
+                                (e.g. AMS-2404 Class 4 → 0.0005″ / 0.001″ / 0.0015″).
+                                Leave empty if no dropdown is needed for this coating.
+                            </p>
+                            <field name="thickness_option_ids">
+                                <list editable="bottom">
+                                    <field name="sequence" widget="handle"/>
+                                    <field name="value"/>
+                                    <field name="uom"/>
+                                    <field name="display_name" string="Display" readonly="1"/>
+                                    <field name="active" widget="boolean_toggle"/>
+                                </list>
+                            </field>
+                        </page>
                     </notebook>
                     <group>
                         <field name="active" widget="boolean_toggle"/>
diff --git a/fusion_plating/fusion_plating_configurator/views/sale_order_views.xml b/fusion_plating/fusion_plating_configurator/views/sale_order_views.xml
index d22540a4..f45f228b 100644
--- a/fusion_plating/fusion_plating_configurator/views/sale_order_views.xml
+++ b/fusion_plating/fusion_plating_configurator/views/sale_order_views.xml
@@ -188,6 +188,22 @@
                        placeholder="Shop-floor workflow instructions (prints on WO / traveler)"
                        optional="hide"/>
                 <field name="x_fc_coating_config_id" optional="show"/>
+                <field name="x_fc_thickness_id"
+                       options="{'no_create': True}"
+                       invisible="not x_fc_coating_config_id"
+                       optional="show"/>
+                <field name="x_fc_serial_id"
+                       options="{'no_create_edit': False}"
+                       optional="show"/>
+                <field name="x_fc_job_number" optional="show"/>
+                <field name="x_fc_revision_pick_id"
+                       string="Revision"
+                       options="{'no_create': True}"
+                       invisible="not x_fc_part_catalog_id"
+                       optional="hide"/>
+                <field name="x_fc_revision_snapshot"
+                       readonly="1"
+                       optional="hide"/>
                 <field name="x_fc_treatment_ids" widget="many2many_tags" optional="hide"/>
                 <field name="x_fc_part_deadline" optional="hide"/>
                 <field name="x_fc_wo_group_tag" optional="hide"/>
diff --git a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_line.py b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_line.py
index 3b637ead..2876e019 100644
--- a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_line.py
+++ b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_line.py
@@ -141,6 +141,25 @@ class FpDirectOrderLine(models.TransientModel):
         compute='_compute_is_missing_info',
     )
 
+    # ---- Sub 5 — Serial / Job# / Thickness -------------------------------
+    # These mirror the SO-line fields and are carried over when the wizard
+    # creates the sale order. Serial stays optional; Job# is left blank
+    # here and gets auto-assigned by action_confirm on the SO.
+    serial_id = fields.Many2one(
+        'fp.serial',
+        string='Serial Number',
+        ondelete='set null',
+        help='Optional. Typing a value offers to create a new serial on '
+             'the fly, or hit "Generate Serial" to auto-sequence.',
+    )
+    job_number = fields.Char(string='Job #')
+    thickness_id = fields.Many2one(
+        'fp.coating.thickness',
+        string='Thickness',
+        domain="[('coating_config_id', '=', coating_config_id)]",
+        ondelete='set null',
+    )
+
     # ---- Computes ----
     @api.depends('quantity', 'unit_price')
     def _compute_line_subtotal(self):
@@ -157,6 +176,22 @@ class FpDirectOrderLine(models.TransientModel):
                 and rec.quantity
             )
 
+    @api.onchange('coating_config_id')
+    def _onchange_coating_clears_thickness(self):
+        for rec in self:
+            if (rec.thickness_id
+                    and rec.thickness_id.coating_config_id != rec.coating_config_id):
+                rec.thickness_id = False
+
+    def action_generate_serial(self):
+        """Create an auto-sequenced fp.serial and assign it to this line."""
+        self.ensure_one()
+        if self.serial_id:
+            return False
+        seq = self.env['ir.sequence'].next_by_code('fp.serial') or 'FP-SN-0000'
+        self.serial_id = self.env['fp.serial'].create({'name': seq}).id
+        return False
+
     # ---- Onchange ----
     @api.onchange('quote_id')
     def _onchange_quote_id(self):
diff --git a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard.py b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard.py
index 8df36270..4406ac2f 100644
--- a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard.py
+++ b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard.py
@@ -279,6 +279,11 @@ class FpDirectOrderWizard(models.TransientModel):
                 'x_fc_start_at_node_id': line.start_at_node_id.id or False,
                 'x_fc_is_one_off': line.is_one_off,
                 'x_fc_quote_id': line.quote_id.id or False,
+                # Sub 5 — carry serial / job# / thickness onto the SO line.
+                # Revision snapshot auto-fills on SO-line create from the part.
+                'x_fc_serial_id': line.serial_id.id or False,
+                'x_fc_job_number': line.job_number or False,
+                'x_fc_thickness_id': line.thickness_id.id or False,
             }))
 
         # 5. Create — stays in draft / quotation. Sub 1: user reviews
diff --git a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard_views.xml b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard_views.xml
index 52ab676c..b9884089 100644
--- a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard_views.xml
+++ b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard_views.xml
@@ -106,6 +106,14 @@
                                     <field name="internal_description"
                                            optional="hide"/>
                                     <field name="coating_config_id"/>
+                                    <field name="thickness_id"
+                                           options="{'no_create': True}"
+                                           invisible="not coating_config_id"
+                                           optional="show"/>
+                                    <field name="serial_id"
+                                           options="{'no_create_edit': False}"
+                                           optional="show"/>
+                                    <field name="job_number" optional="hide"/>
                                     <field name="treatment_ids"
                                            widget="many2many_tags"
                                            optional="hide"/>
diff --git a/fusion_plating/fusion_plating_logistics/__manifest__.py b/fusion_plating/fusion_plating_logistics/__manifest__.py
index 8368ac04..752baaab 100644
--- a/fusion_plating/fusion_plating_logistics/__manifest__.py
+++ b/fusion_plating/fusion_plating_logistics/__manifest__.py
@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — Logistics',
-    'version': '19.0.1.2.0',
+    'version': '19.0.2.0.0',
     'category': 'Manufacturing/Plating',
     'summary': (
         'Pickup & delivery for plating shops: vehicle master, driver '
@@ -41,6 +41,7 @@ Copyright (c) 2026 Nexa Systems Inc. All rights reserved.
     'currency': 'CAD',
     'depends': [
         'fusion_plating',
+        'fusion_plating_configurator',
         'hr',
         'mail',
     ],
diff --git a/fusion_plating/fusion_plating_logistics/models/__init__.py b/fusion_plating/fusion_plating_logistics/models/__init__.py
index dabd8896..e16c51c4 100644
--- a/fusion_plating/fusion_plating_logistics/models/__init__.py
+++ b/fusion_plating/fusion_plating_logistics/models/__init__.py
@@ -11,3 +11,4 @@ from . import fp_route
 from . import fp_route_stop
 from . import fp_chain_of_custody
 from . import fp_proof_of_delivery
+from . import fp_serial
diff --git a/fusion_plating/fusion_plating_logistics/models/fp_delivery.py b/fusion_plating/fusion_plating_logistics/models/fp_delivery.py
index aedba767..b99f2067 100644
--- a/fusion_plating/fusion_plating_logistics/models/fp_delivery.py
+++ b/fusion_plating/fusion_plating_logistics/models/fp_delivery.py
@@ -57,6 +57,23 @@ class FpDelivery(models.Model):
              'Will become a Many2one once the job module ships.',
         tracking=True,
     )
+    # ---- Sub 5 — traceability fields from the source MO --------------------
+    x_fc_serial_id = fields.Many2one(
+        'fp.serial', string='Serial Number',
+        ondelete='set null', index=True,
+        help='Serial copied from the MO when bridge_mrp drafts this delivery.',
+    )
+    x_fc_job_number = fields.Char(
+        string='Job #', index=True,
+        help='Shop-floor job number from the MO. Prints on packing slip.',
+    )
+    x_fc_thickness_id = fields.Many2one(
+        'fp.coating.thickness', string='Thickness',
+        ondelete='set null',
+    )
+    x_fc_revision_snapshot = fields.Char(
+        string='Revision (snapshot)',
+    )
     scheduled_date = fields.Datetime(
         string='Scheduled Date',
         tracking=True,
diff --git a/fusion_plating/fusion_plating_logistics/models/fp_serial.py b/fusion_plating/fusion_plating_logistics/models/fp_serial.py
new file mode 100644
index 00000000..d37b7e68
--- /dev/null
+++ b/fusion_plating/fusion_plating_logistics/models/fp_serial.py
@@ -0,0 +1,25 @@
+# -*- coding: utf-8 -*-
+# Copyright 2026 Nexa Systems Inc.
+# License OPL-1 (Odoo Proprietary License v1.0)
+# Part of the Fusion Plating product family.
+#
+# Sub 5 — attach delivery reverse link to fp.serial. Lives here rather
+# than in fusion_plating_configurator because fusion.plating.delivery
+# is defined in this module, which loads after configurator.
+
+from odoo import api, fields, models
+
+
+class FpSerial(models.Model):
+    _inherit = 'fp.serial'
+
+    delivery_ids = fields.One2many(
+        'fusion.plating.delivery', 'x_fc_serial_id',
+        string='Deliveries',
+    )
+    delivery_count = fields.Integer(compute='_compute_delivery_count')
+
+    @api.depends('delivery_ids')
+    def _compute_delivery_count(self):
+        for rec in self:
+            rec.delivery_count = len(rec.delivery_ids)
diff --git a/fusion_plating/fusion_plating_reports/__manifest__.py b/fusion_plating/fusion_plating_reports/__manifest__.py
index cd430f6d..1b90f70d 100644
--- a/fusion_plating/fusion_plating_reports/__manifest__.py
+++ b/fusion_plating/fusion_plating_reports/__manifest__.py
@@ -3,7 +3,7 @@
 # License OPL-1 (Odoo Proprietary License v1.0)
 {
     'name': 'Fusion Plating — Reports',
-    'version': '19.0.5.0.0',
+    'version': '19.0.5.1.0',
     'category': 'Manufacturing/Plating',
     'summary': 'PDF reports for Fusion Plating: quote, SO, WO, packing, BoL, CoC, invoice, receipt, quality + compliance.',
     'depends': [
diff --git a/fusion_plating/fusion_plating_reports/report/customer_line_header.xml b/fusion_plating/fusion_plating_reports/report/customer_line_header.xml
index 8f4eb2f7..13c20c32 100644
--- a/fusion_plating/fusion_plating_reports/report/customer_line_header.xml
+++ b/fusion_plating/fusion_plating_reports/report/customer_line_header.xml
@@ -24,12 +24,35 @@
         <t t-if="line.x_fc_part_catalog_id">
             <strong>
                 <span t-esc="line.x_fc_part_catalog_id.part_number"/>
-                <t t-if="line.x_fc_part_catalog_id.revision">
-                    <span> (Rev <span t-esc="line.x_fc_part_catalog_id.revision"/>)</span>
+                <!-- Sub 5 — prefer the revision snapshot captured on the line
+                     at save time; fall back to the catalog's current revision
+                     if no snapshot was frozen (old lines from before Sub 5). -->
+                <t t-set="_rev" t-value="(
+                    line.x_fc_revision_snapshot
+                    if 'x_fc_revision_snapshot' in line._fields
+                       and line.x_fc_revision_snapshot
+                    else line.x_fc_part_catalog_id.revision)"/>
+                <t t-if="_rev">
+                    <span> (Rev <span t-esc="_rev"/>)</span>
                 </t>
             </strong>
             <br/>
             <span t-esc="line.name"/>
+            <!-- Sub 5 — print serial / job# / thickness under the line
+                 description when populated. Each on its own row so blank
+                 fields disappear cleanly. -->
+            <t t-if="'x_fc_serial_id' in line._fields and line.x_fc_serial_id">
+                <br/>
+                <small>Serial: <span t-esc="line.x_fc_serial_id.name"/></small>
+            </t>
+            <t t-if="'x_fc_job_number' in line._fields and line.x_fc_job_number">
+                <br/>
+                <small>Job #: <span t-esc="line.x_fc_job_number"/></small>
+            </t>
+            <t t-if="'x_fc_thickness_id' in line._fields and line.x_fc_thickness_id">
+                <br/>
+                <small>Thickness: <span t-esc="line.x_fc_thickness_id.display_name"/></small>
+            </t>
         </t>
         <t t-else="">
             <!-- Fee / freight / non-part line: standard Odoo rendering -->