The product adopts good sensitivity detector, integrated circuit. It gathers automatism, convenient safe, saving-energy and practical functions. It utilizes the infrared energy from human as control-signal source, light turn on when one enters detection field. And, with built in timer it lets you customize the length of time from 5 seconds to 20 minutes, the lights will automatically turn back off when no motion is detected.It can identify day and night automatically. It is easy to install.