Car Door Assembly Specification Example for Aftermarket Retail: Sealed Unit
Car Door Assembly Specification Example for Aftermarket Retail: Sealed Unit
This is a worked specification for car door assembly in a sealed unit programme. It is the document we would send a buyer who asks what exactly they are getting: the material, the dimensions that are actually controlled, the finish, and the checks that happen before anything is packed.
The sealed unit version exists because the duty cycle on aftermarket retail is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually premature wear on the first batch.
Example specification
| Item | Car Door Assembly |
|---|---|
| Application | Aftermarket Retail |
| Version | Sealed Unit |
| Base material | Semi-Metallic Compound |
| Controlled dimensions | 5 key dimensions, recorded per lot |
| Tolerance band | ±0.05 mm |
| Finish | zinc plated |
| MOQ | 3,000 pieces per specification |
| Sampling | 7 working days, 3 days per revision |
| Compliance | REACH |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Semi-Metallic Compound, in this example.
- List the dimensions that are actually controlled and the tolerance on each.
- Name the finish and what it has to survive.
- State the inspection level and who pays when a lot fails.
Processes involved
- robot welding
- surface grinding
- gravity casting
- injection moulding
- precision stamping
- shot blasting
Where this example applies
Programmes that run sealed unit most often specify this build for aftermarket retail. Related applications include light trucks, boat trailers, trailer axles, racing teams, municipal fleets.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 2.5 sampling on the finished lot.
- Finish inspection under agreed lighting.
- Carton drop test on the first lot of a new packing specification.
Questions buyers ask
Can you match an existing sample?
Send a sample and we will reverse-engineer the specification, then produce a counter sample for approval before any bulk starts.
What is the minimum order quantity?
The standard MOQ is 3000 pieces per specification. Mixed sizes inside one shipment are accepted once the total reaches that figure.
How is packing specified?
Individual packing, inner box quantity and carton marking are confirmed at quotation stage so the cartons arrive ready for your warehouse.
What happens if a lot fails inspection?
The lot is re-inspected against the golden sample, and replacement pieces ship on the next available booking at our cost.
Send the specification you are working to and we will confirm what we can match, what we would change and why.
