Reference photo. The factory sample can differ by color, material, and specification.

Smart Products · Contact sensors

Door and window sensor

A two-piece door and window contact sensor whose magnet gap has to survive a real frame, not only a bench jig.

Last updated: September 2026

Source This Product

What this product is

A door and window sensor is two small housings and a magnet, and the sourcing question is the gap those two pieces will still accept when a door sags. A pair that looks closed on a flat bench can chatter on a real frame. Factories that already export this two-part shape can change housing color, a pad-printed logo, and a one-page insert. They should not be asked to design a new radio on the first order. The brief needs the maximum gap you will accept, whether the unit is a battery contact or a wired pair, and which radio is actually on the board. Most opening orders stay with the factory app. A private app is software work, quoted apart from the plastic. Mount the sample on a door that is slightly out of plane and write down the distance that still reads closed. False alarms belong in that same note. The band on this card is an indicative ex-works range for a common battery contact pair, before freight. Destination radio rules and the cell are outside that range. Do not print a detection distance the sample missed.

Indicative sourcing numbers

These are desk estimates for a conversation, not a factory invoice and not a retail offer from this website.

Indicative China sourcing price: $2.80 to $6
Suggested retail range: $14 to $26
Estimated gross margin: 32% to 50%

Indicative estimates only. Actual margins vary by supplier, quantity, specifications, shipping, duties, taxes, marketplace fees, advertising and destination market.

Why it is interesting

The two-piece contact pair is already a common export, so the first decision is gap and radio, not a new enclosure.
A door that is slightly out of plane tells you more about the magnet than a bench jig does.

What to specify

Form: Two-piece magnet and contact body
Gap: Closed-state gap tested on a real door
Radio: Protocol confirmed; rules outside the unit estimate
App: Factory app on most first orders
Power: Cell type confirmed; battery rules quoted apart

Customization and private label

A shell logo and a printed insert fit a first order that stays on the factory app; a private radio stack or a new case is a different project.

Some customization is realistic on this kind of product. Private label packaging is often possible once artwork is approved. Read how private label manufacturing in China is handled, and when a new product needs the OEM/ODM path.

How the desk would source it

Note 1. Record the gap that still reads closed on a real frame, and put that number in the spec.
Note 2. Treat the factory app as the first-order path. A private app is a separate scope from the housings.

The usual path is the same as other China factory sourcing: confirm the spec, compare factories, sample, then inspect before shipment. China supplier verification and China quality inspection are available. Goods can be received at the Xiamen warehouse and moved through China warehouse consolidation or sea, air, and express freight.