Light Efficient Design LED-8088M57 Shoe Box/Wallpack LED Retrofit Lamp Light Bulb Ballast Bypass Compact design delivers wide, even light distribution when retrofitted into shoe box or wall pack fixtures. Easy to install, reliable retrofits provide an energy savings up to 80%. Rotatable E39 Screw Base insures that light output is directed to where it is needed. Delivers higher delivered lumens and desired result compared to shoe box retrofits using generic LED corn lamps. Safety rated and heat tested within fully enclosed fixtures from -40 to +122F ambient temperatures. 50W LED replaces Metal Halide (MH) or High Pressure Sodium (MPS) High-intensity discharge (HID) Lamps up to 175W. Advanced Active Cooling technology includes dynamic temperature monitoring, computer designed high efficiency heat sink and long life active cooling fan. Superior heat management results in consistently higher performance and long LED life.