Car Bluetooth Device Specification Example for City Buses: Heavy Duty
Car Bluetooth Device Specification Example for City Buses: Heavy Duty
This is a worked specification for car bluetooth device in a heavy duty 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 heavy duty version exists because the duty cycle on city buses 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 Bluetooth Device |
|---|---|
| Application | City Buses |
| Version | Heavy Duty |
| Base material | Stainless Steel |
| Controlled dimensions | 4 key dimensions, recorded per lot |
| Tolerance band | ±0.2 mm |
| Finish | powder coated |
| MOQ | 3,000 pieces per specification |
| Sampling | 14 working days, 5 days per revision |
| Compliance | ISO 9001 |
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
- precision stamping
- assembly line testing
- laser cutting
- surface grinding
- shot blasting
Where this example applies
Programmes that run heavy duty most often specify this build for city buses. Related applications include dealership service, camper conversions, municipal fleets, city buses, trailer axles.
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
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.
What testing is included?
Standard lots ship with dimensional and hardness reports. ISO 9001 documentation is issued with the shipment when your market requires it.
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 3000 pieces per line.
Send the specification you are working to and we will confirm what we can match, what we would change and why.



