This wireless motion detector is powered off of a single 9 volt battery. It sends a signal to the base unit when motion is detected. This are ideal for a staircase or open room. When motion is detected, it trips the alarm.

Typical detection range is 15 to 20 feet.

Please note:
You may use an unlimited number of any combination of addons. However, the base unit is REQUIRED for any of the addons to function.