4FT LED Linear Explosion Proof Light, Class 1 Division 2, 7000 Lumens, 50W, 5000K, Beam Angle 120 degree, 100 277V, R Series Product Category_Ultraviolet Lights It has excellent heat dissipation It has excellent heat dissipation and an excellent lighting effect Internal solid state transfer switch automatically connects the internal battery to lamp heads for minimum of 90 minute emergency illumination The optional battery backup system provides a minimum of 90 minutes operation after AC power is lost during an emergency The combination of the style and design of new LED technology with the ruggedness and durability of a hazardous location fixture makes it ideal for retrofit of existing HPS MH and offers higher efficacy for energy savings