1、Quick Response: This sensor operates with a quick response that when there is opening or closing, it will send the alarm to you automatically in 10s. 2、Wide Application: This sensor is very suitable for front doors, window, baby rooms, garages, etc. To ensure the safety of your belongings! 3、Data Storage: All alarm record history can be viewed in the application, you do not need to worry about losing any records. 4、Voice Operation: Issue a voice command to check the opening or closing status without putting down or picking up the phone. When the sensor is triggered, your voice device will work as a bell, siren or alarm, very practical! 5、Wide Compatibility: The for Google Assistant is compatible with this sensor, making use more convenient for you! 2 x Sensor2 x Installation Sticker3 x Screw3 x Expansion Tube  1 x Manual Item Type: Door Window SensorMaterial: ABSBattery Type: LR03 1.5V, AAA x 2 (not included)Standby Current: 8uALED Indicator: RedWireless Frequency: 2.4GHz