Tips for purchase: This product is Zigbee version, Users must have/already bought a tuya zigbee hub to operate. If without a zigbee hub, then such model will not work. Product Features: [Instant Notification]]Push instant notification to your phone immediately when the door or window is opened or closed. Keeping you informed all the time. Alarm Recording]]Support checking open/close records and battery levels on the app. Never worry about miing any important moments or running out of battery. [Low Voltage Remind]]When the battery level is low, it will automatically remind you to change batteries, never worry about running out of battery. [Intelligent Linkage]]The door sensor can be linked with other smart devices in the home and make your home more smart after connected with zigbee hub. Low advantage design to ensure long-term battery life. For example, the light will be on automatically when the door is open. (Note that the light needs to be used with WIFI switch). [Third-party voice support]]This sensor supports Alexa and Google Home Aistant. Easy to Install]]Small size,easy to install Adhesive installation,can be flexibly placed in various doors, windows,drawers,etc,without destroying the appearance and structure of the original furniture. Specifications: Input voltage:3V LR03 Standby current :≤10uA Alarming current :≤15mA Low-voltage notification :≤2.5V Zigbee frequency:Zigbee 3.0 Magnetic control distance:≥15mm Battery: DC 3V LR03(AAA battery,not included) Alarm mode: mobile phone APP notification push(Ewelink) Product package included: 1xWIFI door Sensor (Not include battery)1xsticker1xUser manual