Sourcing fitness bands

Strap material and grade. Thermoplastic polyurethane, silicone, nylon and leather all behave differently against skin over months of sweat, sunscreen and washing. Ask for the material grade and the supplier of the compound, not just "TPU" — the difference between compounds of the same family is exactly where a cost reduction hides.

Metal parts. Buckles, pins, keepers and the case back are the parts in longest contact with skin, and prolonged skin contact is a regulated condition in several markets: the European restrictions on nickel release apply to articles intended to be in extended contact with the skin. Specify the base metal, the plating and its thickness, and require test evidence for the article you are buying.

A generic supplier declaration is not test evidence. Ask for a report that names your model and the parts tested, from a laboratory, and check that the applicant is the company invoicing you.

Colourants and finish. Dyes and surface treatments are the other skin-contact variable, and dark strap colours are the ones that most often produce complaints in hot markets. If your market is hot and humid, make ageing under heat, humidity and sweat a specified test rather than a hope.

Mechanical. The lug or pin retention and the clasp are what lose a band, and a lost band is a total loss for the customer. Specify a pull test with a defined load, and test it on samples that have been aged rather than only on new ones.

Ask whose app it is, first. At this price a band is a client for a platform owned by the reference design's owner. The app, the account system, the cloud storage and the update mechanism are usually theirs, and every unit you sell depends on all four continuing to exist.

Then ask the questions you will be asked later. Under whose developer accounts is the app published? In which country is the data stored? What is the retention period? Is there a data-processing agreement you can actually sign? Can the app be branded for you, and if so, is that a separate build with its own maintenance?

And ask the one nobody asks: what happens to bands already sold if the factory moves to a different platform? The honest answer is often that they stop syncing, and it is your brand on the product when they do.

Firmware updates. Whether the band can be updated at all, who builds the firmware, and what the path is for a fix. A band that cannot be updated is a product whose bugs are permanent.

None of this makes a platform band the wrong choice — it is the normal and often correct commercial decision at this price. What is wrong is not knowing, because every one of these answers changes what you can promise a customer.

Keep the claims to fitness metrics. The intended-purpose principle that decides whether a wearable is a regulated device applies to bands exactly as it does to watches, and the factory's feature list was written for a different market. Decide your claims in writing and require the removal of the rest from packaging, manual, app and firmware strings.

Sensor validation instead of a number. Optical heart rate varies with skin tone, tattoos, hair, fit and motion, and step counting varies with wrist position and gait. No accuracy percentage appears on this page. Validate on several people, in motion, against a reference you trust — and pay attention to how the band behaves on a thin wrist, which is where a poor optical seal shows first.

Battery and charging. Cell manufacturer and capacity, and how the band charges — a proprietary clip or cradle is a spare-parts liability and a common source of returns when the contacts corrode after sweat exposure. Specify the contact plating.

Water rating. An IP or depth rating is the outcome of a defined test on a defined unit, so ask which test, on which model, by whom, and read the report — and confirm the rating still applies after the strap and the charging contacts have been assembled.

Lithium transport documentation applies as it does to any cell-carrying product; the guides on watt-hour conversion and shipping lithium batteries by air carry those thresholds and this page deliberately does not.

Business licence and business scope (经营范围) first, then the platform question, then materials evidence. In this category the platform and the materials answers matter more than the specification sheet, and both are questions rather than numbers.

Wear-test properly: several people, several weeks, through exercise, sleep and showering, in the climate you sell into. Skin reactions and strap degradation only appear over time, and they are the complaints that damage a brand rather than merely costing a return.

Age the strap deliberately — heat, humidity, sweat solution, sunscreen — and then repeat the pull test. A strap that passes new and fails aged is the product you are actually shipping.

Test the app as a customer: fresh phone, your market's language, read the permissions and the privacy policy. Then take one band apart: battery marking, sensor assembly, how the case is sealed and how the lugs are anchored.

Every supplier on this site is a manufacturer, and the registered-scope check is one of the things confirmed before a listing goes live.