Features: 1) Built-in sensor: The host is passive infrared sensor itself 2) Built-in alarm: when the host sense the intrusion, and will start up the built-in siren automatically 3) Wireless transmission: the host will send signal to the monitor station or the alarm host 4) Stand by battery: Built-in adapter and rechargeable battery in the host 5) It can directly plug to the jack or can be used without external power 6) Remote control, you can use the remote controller to turn on or turn off the host Technical parameters: 1) Power voltage: AC 220V 2) Launch current: 15mA 3) Alarm sonority: 110dB 4) Launch frequency: 315/433MHz