Car Audio System Specification Example for Construction Equipment: Premium Line
Car Audio System Specification Example for Construction Equipment: Premium Line
This is a worked specification for car audio system in a premium line 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 premium line version exists because the duty cycle on construction equipment 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 | Construction Equipment |
| Version | Premium Line |
| Base material | Magnesium Alloy |
| Controlled dimensions | 5 key dimensions, recorded per lot |
| Tolerance band | ±0.05 mm |
| Finish | zinc plated |
| MOQ | 2,000 pieces per specification |
| Sampling | 10 working days, 3 days per revision |
| Compliance | RoHS |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Magnesium Alloy, 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
- sintering
- powder coating
- rubber vulcanisation
- cold forging
- anodising
- injection moulding
Where this example applies
Programmes that run premium line most often specify this build for construction equipment. Related applications include off-road bikes, agricultural trailers, city buses, utility trailers, aftermarket retail.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 4.0 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
Do you handle mixed containers?
Yes. Most programmes consolidate several part numbers into one container to keep freight sensible at 2000 pieces per line.
Can the specification be held on file?
Yes. Once approved, the specification is recorded against your part number so a reorder reproduces the RoHS-compliant build instead of a fresh interpretation.
What is the minimum order quantity?
The standard MOQ is 2000 pieces per specification. Mixed sizes inside one shipment are accepted once the total reaches that figure.
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.
Send the specification you are working to and we will confirm what we can match, what we would change and why.



