CPL Filters remove unwanted reflections by selecting which light rays enter your camera lens. The increases color saturation bring better clarity and contrast while leaving the overall color balance unaffected. This CPL is using double-sided coating AR to better increase their transparency and to reduce reflective phenomenon. BAF - Black matt aluminum satin finish almite frame reduces reflections. LPF: Ultra think low profile frames to help avoid vignette on super wide angle lenses. BRG: Black rimmed glass reduces light reflections around the filter edge. KEF: Equipped with a knurling edge for easy attachment and removal. UVC: Filter cases are UV protected to further lengthen the life of filters. SMC: Super multicoated filter greatly reduce lens flare and ghosting caused by reflections. Glass manufactured by AGC Corporation Japan.