Conformal coated cadmium sulphide photocell resists effects of moisture and airborne contaminants, photocell responds to the light spectrum near to that of a human eye Delayed response prevents false switching due to light from vehicles or lighting, etc Polycarbonate housing and window, UV stabilized for permanent color, provides high impact performance, flammability resistance and electrically safe operations Locking prongs - solid brass for maximum corrosion-resistance and electrical conductivity Power consumption under 1 W