We offer this photo control primarily as an accessory to our line of LED dimming power supplies. It is shown installed on one of them in one of the pictures of this product. Provides dusk-to-dawn lighting control. The thermal type controls feature a cadmium sulfide photocell and sonic welded polycarbonate case and lens to seal out moisture. The design utilizes a dual temperature compensating bimetal and a metal film resistor for reliable long life operation over ambient temperature extremes. The thermal type photo controls provide a delay action which eliminates loads switching OFF due to car headlights, lightning, etc. Includes mechanism only.