This fully automatic Motion Detector (PRI) capable of detecting up to 360 degree coverage area. If any body enters in the covered area the system became on. During the day the built - in photocell saves electricity by deactivating the Load. An adjustable timer lets you selects how long the floodlight stays on and the sensitivity adjustment allows you adjust the detection distance from 3m to 12m. So you can save a lots of elctricity by using this unit.