Includes one 70 watt high pressure sodium medium base bulb. Built in photocell. 17,000 sq. ft. light coverage area. 24,000 hr. bulb life. 13.38 in. W x 12.63 in. D x 15.75 in. H (10.52 lbs.). Photo controls ensure optimum night-time detection on our dusk-to-dawn utility lights. Heath zenith lights activate with the absence of daylight for true night-time only lighting.