The PowerSun UV is a self ballasted mercury vapor lamp which emits UVA, UVB, and heat all in one lamp! Fits into a standard ceramic socket. (No ballast needed.) The 160 watt projects UVB up to several feet from the lamp's surface and is ideal for Large terrariums or bird aviaries. Features include quality nickel plated threads to prevent against corrosion, and a full one year warranty!