Irix Edge Neutral Density (ND) filters are an essential tool for long exposure photography and depth of field manipulation. They reduce the light passing through the lens by 4 stops (4EV) and help create amazing, surreal images. Its additional waterproof and oil-repellent NANO coating prevents stains, fingerprints and allows use in extreme weather conditions. Its low-profile frames and knurled edges provide very good grip and functionality with an aesthetic design that harmonizes with all Irix products.