True Lumen"s Actinic 460 helps both LPS and SPS corals become brighter, Produces excellent color rendition and usable light due to a high blend phosphor mix, Ideal for saltwater reef and fish aquariums, Recommended by Current USA as a replacement for the discontinued Current USA Replacement SlimPaq 34"", 460nm Actinic, 39 Watt, T5, HO Fluorescent Lamp (2133), 460nm Actinic Blue, The TrueLumen T5 bulbs will work in any T5 fixture, as long as you are using bulbs of the same wattage and length as those currently in your fixture, Dimensions: 36"", SKU: RYLHC1607