Use Bridgelux 45mil LEDs, to ensure the high light output , On the back side. This is round position there is for install the photocell, only need to make a drill, and       install the photocell. With this photocell. Then no need control the light ON and OFF, it can by itself,           and when light enough, the lamp turn off, so it can save more energy ,  Meanwell driver, 5 years warranty, no worried about the quality , 60% energy-saving is more than traditional light , No mercury or lead; environmental protection , CE ROHS certificate ,  the retail of the holder can be adjustable, so it can fix to 50 to 70MM pole arm , Waterproof design,  and use outdoor, it is IP65 , Classic design, the radiators on the back side ,good for the heat dissipate , Multi LEDs design to make the LED full of the radiator, so that the heat can be out very fast, to keep          the whole temperature low, it is good for the life time of the lamp , This model is very cheap economy. Cost low, a lot of customer like it