Solar road stud is used on Highways, at parking lots, also used on curves on roads. Material:Cast Aluminum, Plastic, Glass. Solar Panel Voltage:2V/100-200mAH, 3.5V/78-120mAH and etc. Solar Panel Material:Monocrystalline silicon or polycrystalline silicon. Battery Voltage:1.2V/600-800mAH, 2.4V/600mAH, 2.4/650mAH.