HD GLASS• High Density Sharp Cut UV Glass• Chemically Enhanced Optical Glass is 4x StrongerHD COATING• 8-layer Anti-Reflective Multi-Coating• Water & Oil Repellent, Scratch & Stain ResistantHD FRAME• Wide-Angle Lens Compatible Ultra Thin Frame• Glass Mounted with High Pressure Press TechnologyA multi-purpose fine-weather filterAbsorbs the ultraviolet rays which often makes outdoor photographs hazy and indistinct. A multi-purpose, fine-weather filter for color as well as black and white films. Also serves as a permanent lens protector.