DETECT OPEN/ CLOSE STATUS: It detects open/close status of the door/window, and use it on doors, windows, cabinets, drawers, mailbox or anywhere you want to notified when it's opened or closed. Catch every activity and send alert to your smart phone. Help you to keep an eye on the security of your house anytime, anywhere. TAMPER ALARM FUNCTION: Dont worry about someone trying to steal or destroy the door sensor from door/window to break into your house. The WiFi door sensor with tamper alarm function, you will get the notification immediately. Time to update your home security! SUPPORT TWO WAYS CHARGE: Battery powered and USB charged.The battery Type Is CR123A, the battery is replaceable. USB port is not for charging the battery. You want to the sensor can work longer, then use USB charge. ONLY SUPPORT 2.4G WIRELESS TYPE: It connects to your smart phone via App under 2.4G Wi-Fi environment. If your WiFi router only supports 5G, the device wont connect. THIRD PARTY SUPPORT: Work with Alexa and Google home. It is able to works with other third party home wifi smart device to improve your home security. Tech guy can D.I.Y to discover more usage scenarios, and create a smart scene to let the WiFi devices work together.