The Intermatic IOS-DOV-WH is the passive infrared sensor switch that works by detecting the difference between heat emitted from the human body in motion and the background space. The sensor switch can turn a load ON and hold it as long as the sensor detects occupancy. After no motion is detected for the set time delay, the load turns OFF automatically. The sensor switch has one relay (equal to a single pole switch), and it also includes an Ambient Light Level Sensor.