Aqara Door and Window Sensor T1, Mini Wireless Contact Sensor for Smart Home Security and Automation, Requires Aqara Hub, Zigbee 3.0, Works with Apple HomeKit, Alexa, IFTTT

The Aqara Door and Window Sensor T1 detects the open and close state of doors or windows through the distance between the sensor unit and the magnet. It consumes a minimal amount of energy. No tools are required, just stick it to the desired place and use it in a dozen of possible use cases.
Note: Requires an Aqara Hub (sold separately) and a secure 2.4GHz Wi-Fi connection (Hub M2 also supports Ethernet). Not compatible with hubs from other brands.
Connection Range: For stable performance, keep the sensor within 400 inches of the Aqara Zigbee Hub, and ensure the hub is within the same distance from your Wi-Fi router. Both must be on the same local network.
Security Alerts & Automation: Get instant alerts on your phone and trigger alarms on the Aqara Hub if a door or window opens unexpectedly. Easily automate other Aqara devices based on door or window status for enhanced home security.
Wide Compatibility: Works with most doors, windows, drawers, and cabinets with gaps up to 0.86 inch. Sensor size: 1.61×0.87×0.43 in; Magnet size: 0.79×0.39×0.39 in. Ensure installation surfaces are flat and adhesive-friendly.
Hands-Free Voice Control: Compatible with Apple HomeKit, Alexa for a hands-free experience.- no need to go downstairs or pick up your phone again. You’ll always know whether your home door is opening or closing. (Not compatible with SmartThings.)