This HOMESAFE WIRELESS HOME SECURITY SENSOR is a double sensor that detects vibration and when your door/window has been opened. It has a wireless radio frequency range of 300 feet. When triggered the RF signal activates the alarm. Uses one 9-volt battery (not included). Easily protect every window and door of your home.

This is an additional door/window sensor only for the HA-SYSTEM (item 30-300).