Screw-socket high intensity discharge metal halide bulbs For metal halide mogul socket fixtures 175, 250, and 400 watt metal halide bulbs ideal for reef aquariums Screw-socket metal halide bulbs in a variety of color temperatures and wattage to reproduce natural light conditions found in the ocean. Significantly brighter than other types of bulbs, metal halide bulbs can be used alone or with Actinic bulbs for a bluer effect. Use with any appropriately sized mogul socket metal halide lighting unit. Available in: 175 watt 10000 degreeK 250 watt 10000 degreeK 400 watt 10000 degreeK 175 watt 15000 degreeK 250 watt 15000 degreeK 400 watt 15000 degreeK 175 watt 20000 degreeK 250 watt 20000 degreeK 400 watt 20000 degreeK Handle bulb by socket end only, DO NOT touch bulb. Please click on "More Information" for further details and safety and handling instructions.