Smarthus

Detects if a window or door is closed in real time, Peel & Stick, Local & Remote Alarm, 2 Years Battery Life, Zigbee, Install the Aqara Door and Window Sensor on your door or window at home to always know if they are opened or closed. Do you often forget to close your doors or windows? Just use your phone to find out, can be used through HomeKit with the Aqara Hub, 41 × 22 × 11 mm

Get real-time security notifications whenever a door or window opens with the Contact Sensor. Installation is easy, simply mount it to any door or window fram in your home to stay secure. Works with the Ring Alarm system

T2 is a 100% Wire-Free Open/Close Detector, 2 years batterylife (exchangeable CR2450), connects to the C6T camera using it as Hub (not included)