Wireless Door or window magnetism switch

It is used to protect door or window. It will send signal to alarm console when door or window is open.
Functions and Specification:
1.The sensor matches with a magnet, when both parts moves away, it will send signal to alarm console immediately.
2.The wireless transmitter adopts SAWF for stable emitting.
3.The distance between magnet part and sensor part is not beyond 20mm.
4.Low power alert and alarm.
5.Power supply:12V 23A(Laminated battery)
6.Frequency:433MHz
7.Transmitting distance:250m (open area)
8.Dimension:37*65*17mm