Hoya PRO1 Digital is a multi-purpose fine-weather filter/ which absorbs the ultraviolet rays/ which often makes outdoor photographs hazy and indistinct. This multi-purpose/ fine-weather filter for color as well as black and white films also serves as a permanent lens protector.<br />DMC: Digital Multi-Coated Filter. Greatly reduces the appearance of lens flare and ghosting caused by reflections<br />BAF: Black Almite Frame. a black matte aluminum satin finish almite frame which reduces reflections<br />BRG: Black Rimmed Glass. reduces the chance of light reflecting off the edge<br />LPF: Low Profile Frame. Ultra Thin Frames to help avoid vignetting on super wide angle lenses. These frames are do hold a lens cap<br />KEF: Knurling Edge Frame. These filters are equipped with a straight knurling edge for non-slip/ easy attachement and removal<br />