Please read this before you buy1. This sensor must match the for xiaomi multifunctional gateway or for Aqara gateway hub ( need to be purchased separately ) to use.2. for Aqara gateway hub is required to make this sensor to work with HomeKit.Highlights● for Aqara smart door and windows sensor for daily security● ZigBee wireless connection● Trigger and alarm: Connected with for Aqara Hub, it will trigger alarm when someone break into.● Away from home mode: Smart linkage with other smart home devices. If someone broke into, the bell will ring and the IP camera ( not included ) will take video.● Can work with for Apple Homekit, for Mi Home, for Aqara Home● Small size, easy to install● Model: MCCGQ11LM● Battery: CR1632 (included)● Wireless Protocol: Zigbee● Maximum Detection Distance: 22 mm● Operating Temperature: -10℃~+45℃(14℉~113℉)● Operating Humidity: 0 - 95%RH, non-condensing● App: for Apple Home app (iOS 10.3 or later), for Aqara Home app (Android 5.0 or later, iOS 10.3 or later), for Mi Home appTwo steps to connect with the APP:1. Open the APP,choose"Add More" in the main interface, add the window door sensor2. Press the "Reset" button of the sensorColor: WhiteMaterial: plasticPackage Contents:4 * Door Window SensorOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.