Select grade fix mount electronic photo control, stem mount, side lens. Non drift silicon light sensor with IR filter. DC relay with zero crossing circuitry for extended life. 15 year design life. Conformal coated PCB. Exceeds 10000 on/off switching cycles. Ideal for single or multi fixture HID and LED installations up to 1650 W, 277 VAC. 255J MOV surge protection element. 1/2 inch 14 NPSM threaded stem fits standard outlet boxes and wall packs.