Wireless door sensorDescriptionName: Wireless Door/Window Magnetic ContactModel:XSJ-87XSJ-87 can detect opening of any door or window. The magnet can be installed on the door or window while the transmitter can be installed on the frame. When the magnet moves away from the transmitter more than 1/2" distance,Website:http://www.home-security-life.com, the transmitter emits a signal to the alarm main unit to set off the alarm.Main Features:•Wireless signal transmission•Generally set in Perimeter zone or Motion zone•If any door or window is opened, it will transmit the alarm signals to the alarm host•Sensor trigger and low voltage indication by LED indicator•Easy installation•Compact size•CE, RoHS & FCC certifiedTechnical Parameters:Operating voltage: DC 12V Standby current: