D3d security the wireless pir motion detector is an input device, the pir-100b pir motion detector is designed to provide detection of criminal intrusion through door frames and window frames into a protected area by sensing infrared energy (heat) emitting from an intruder’s body moving through a protected area. The motion sensor is commonly referred to as a pir, which stands for passive infrared. Upon detection of intrusion, the pir-100b automatically generates an alarm signal to control panel. The sensor also provides a tamper contact output. The unit is rf and emi immunity to interference produced by radio device. The unit is can be wall-mounted by means of a bracket. Note: Please note this listing is for the pir motion sensor. This pir motion sensor works with d3d home security system, which need to be bought separately. Main function and feature: Internal wireless antenna, long distance transmission learning code, easy to assign to the alarm panels tamper switch for protecting the to avoid opened newly-developed dual element passive infrared sensor unit wireless transmitting digital signal to control panel intelligent mcu inside, eliminate false alarm low power alert by buzzer sounds micro controller temperature analysis and automatic temperature compensation for best summertime detection tightly-mated bug guard to protect the sensor optics from insects, spiders and dust selectable detection sensitivity (standard/high) for different environmental requirements smt adopted, rf and emi immunity low power consumption, long battery life adjustable detection time span(4 minutes or 8 minutes) just simply dial in to the d9, change the status to arm/stay/disarm by missed call, or create voice conversation automatically package included 1 wireless pir sensor 1 9 volt battery.