Car Audio System Specification Example for Three-Wheelers: Sealed Unit
Car Audio System Specification Example for Three-Wheelers: Sealed Unit
This is a worked specification for car audio system 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 three-wheelers is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually a specification nobody had written down.
Example specification
| Item | Car Audio System |
|---|---|
| Application | Three-Wheelers |
| Version | Sealed Unit |
| Base material | Stainless Steel |
| Controlled dimensions | 4 key dimensions, recorded per lot |
| Tolerance band | ±0.5 mm |
| Finish | powder coated |
| MOQ | 1,000 pieces per specification |
| Sampling | 7 working days, 3 days per revision |
| Compliance | TUV |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Stainless Steel, 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
- injection moulding
- ultrasonic cleaning
- precision stamping
- cold forging
- heat treatment
- shot blasting
Where this example applies
Programmes that run sealed unit most often specify this build for three-wheelers. Related applications include rental motorcycles, light trucks, aftermarket retail, scooter fleets, fleet maintenance.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 1.5 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 the specification be held on file?
Yes. Once approved, the specification is recorded against your part number so a reorder reproduces the TUV-compliant build instead of a fresh interpretation.
How long does sampling take?
Samples leave the factory in 7 working days, and each revision round adds about 3 days once you have seen the first piece.
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.
Do you handle mixed containers?
Yes. Most programmes consolidate several part numbers into one container to keep freight sensible at 1000 pieces per line.
Send the specification you are working to and we will confirm what we can match, what we would change and why.
