The CF250 from Bigblue is designed for use with the CF250 Dive Light, and consists of a blue and deep blue filter and a yellow blue-barrier filter mask. This kit can be used to illuminate the fluorescent proteins in the corals, which are invisible to the naked eye. The blue filter and deep blue filter is used to precisely match the coral fluorescence wavelength, and the yellow blue-barrier filter mask is used to increase the intensity of the colors emitted by the corals. The snap-on and flip-open filters allow you to easily switch between blue and white light to accommodate changes in dive conditions. This kit is suitable for night divers, resorts, science institutions, ecological monitoring groups and specialty photographers.