Metal halide light bulbs come in many shapes and sizes. We stock many versions of the BT37 & ED37 type metal halides. Metal halide lamps are very common in warehouse high bay fixtures, flood lights, commercial wall packs and parking lots. These lamps come in 250, 400, 750 & 1000 Watts. "BT" stands for blown tubular and you will notice these type metal halide bulbs have a small extended round tip on the top to support the metal tabs inside the lamp. The other type is an "ED" which stands for elliptical dimpled. The graphic below is a great example of the differnt styles of metal halide lamps available. If you are having trouble figuring out which lamp you need, please click the Live chat button or give us a call!