It is a Photosensitive Diode Relay Module. The light brightness detection, detection, through the potentiometer adjustable brightness detection valve, with relay, to do a variety of brightness detection switch, can control all kinds of lights, night open automatically, and automatically extinguished daytime car supplies control and automation equipment. (Compared with the photosensitive resistance, the direction is relatively good, can sense the fixed direction of the light source, detection of the light front of the photodiode is in front of the light, it is difficult to detect the surrounding, often in the light-seeking function.) Package Includes: 1 x Photosensitive Diode Relay Module. Category: Relay