They report an opening, which is earlier than reporting a presence · review
A Zigbee door and window sensor with a tamper alarm, which SONOFF states can run local scenes between Zigbee devices without the internet — provided a compatible hub is present.
The conclusion The technically right sensor at the price of a cheap one. It needs a Zigbee hub, and if you have one it is the obvious choice.
Contact sensors are small, numerous and battery powered, which is exactly the job Zigbee was designed for.
Battery life measured in years rather than months, because the radio wakes, sends a few bytes and sleeps. A mesh, in which every mains-powered Zigbee device in the house extends the range for the battery ones. And no traffic on your Wi-Fi, which matters when there are a dozen sensors.
Wi-Fi sensors are more convenient to set up and worse at all three.
SONOFF states the sensor can drive scenes between Zigbee devices locally, with no cloud involved. A door opening switches a light with the broadband down, and nothing about the state of your doors leaves the building. For a security sensor, both halves of that matter.
Removing the sensor is itself reported. Without it, taking a sensor off a frame is silent, and silence is what an intruder is trying to produce.
A Zigbee hub — SONOFF’s own, or Home Assistant, or SmartThings, or any Zigbee coordinator. That is the strength as well as the requirement: this is a standard rather than one company’s protocol, and the sensor is not stranded if SONOFF stops caring about it.
Anybody who already has Zigbee. It is the sensor to choose once a hub exists.
Not found on the American Amazon store, where the buy link falls back to a local search rather than to a page that does not exist.
Prices and availability are what Keepa reported on the date this page was updated; both move.
| Protocol | Zigbee 3.0; works with Alexa and Google Assistant through the hub |
|---|---|
| Requires | A compatible Zigbee hub |
| Security | Tamper alarm |
| Operation | Local scenes between Zigbee devices without cloud, stated by SONOFF |
| Gap | Sensor and magnet up to 20 mm (0.79 in) apart, stated by SONOFF |
| Battery | CR2477 coin cell, over 5 years stated |
| Mounting | Two 3M adhesive pads supplied |
| Amazon reference | B0C1G7W72B |
| EAN | 6920075740646 |
Three reasons. Battery life measured in years rather than months; a mesh where each mains-powered Zigbee device extends the range; and it is not competing for your Wi-Fi. For sensors — small, numerous, battery powered — Zigbee is the technically right answer and Wi-Fi is the convenient one.
That the hub can act on the sensor without asking a server. A door opening can switch a light with the internet down, and nothing about your house leaves it. On a security sensor that is worth having for both reliability and privacy.
No — Zigbee is a standard, and this sensor works with Home Assistant, SmartThings and other Zigbee coordinators. That is the main advantage over the Wi-Fi sensors here, which usually work only with their maker's app.
7.5/ 10
The technically right sensor at the price of a cheap one. It needs a Zigbee hub, and if you have one it is the obvious choice.
A reference exists on these Amazon stores: France, Germany, Italy, Spain, United Kingdom. Listed is not the same as in stock — availability changes daily.
Details checked on September 2, 2026.
A Zigbee household — Home Assistant, SmartThings or SONOFF's own hub — wanting cheap, reliable contacts.
Amazon reports what buyers took in the month before this page was last checked: at least 300.
The figure is a floor, rounded by Amazon, and read through Keepa — it says what buyers picked, not what a maker claims.
Specifications: the manufacturer sheet for home security products and the matching Amazon product page. Prices and availability: Keepa. Every figure on this page names its source.
For Smartvest Pro · wireless opening detector · triggers configured scenarios · doors and windows
The opening detector for ABUS's Smartvest Pro alarm. It reports unauthorized opening of doors, windows and patio doors, and triggers whatever scenarios have been configured on the panel.
Best for: An ABUS Smartvest Pro system being extended door by door.
90 dB standalone siren · 3.54 × 1.18 × 0.79 in and about 0.08 lb, both published · 2 AAA, NOT included · a three-step install written out · five units for ten dollars · no gap figure, no battery life, no tamper detection
Five alarms for ten dollars with their dimensions and weight published — two figures the cheapest sirens here usually leave out.
Best for: Five openings on a tight budget, where the body has to be measured against a shallow frame first
≈ $10
120 dB alarm or chime, switched on the side: OFF / chime / alarm · 4 LR44 cells SUPPLIED · a battery TEST BUTTON and a low-battery LED, the only test button on this shelf · double-sided tape included · no gap figure, no battery life, no tamper detection
The only sensor here with a button that tells you the battery is still good — which on an alarm nobody checks is worth more than it sounds.
Best for: A household that wants a chime for the back door in the day and an alarm on it at night
≈ $19
