The Photocell Controllers by Custom Automated Products are perfect when you need to turn a device on only during daylight hours or only at night. A photocell senses whether it is day or night, and turns the device plugged into it on or off depending on which model you are using. The Day On Timer turns on whatever is plugged into it during the day when the lights are on. The Night On Timer turns on the device during the night, when the lights are off. Photocell Controllers are rated for 15 amps @ 120 volts. 3 year warranty.