Buy the new XH-M131 DC 12V Light Control Switch Photoresistor Relay Module. The Light Detection and brightness detection, detection can be adjusted via potentiometer brightness valve point comes relays, and do all kinds of brightness detection switch, you can control all kinds of street lights automatically turn on at night, during the day and automatically turns off and car supplies control and automation equipment.Using the photoresistor induction light intensity comes with the relay and direct control load. It has a Distribution bit sensitivity adjustment. The start relay threshold is set by adjusting the potentiometer. 12 V power input is designed for relay board regulator transistors to provide sensors and is Used to make the product more stable and reliable. It has four fixed bolt hole for easy installation.