Top Features Waterproof Oil and; Anti-scratch coating . German SCHOTT optical glass . Multiple grinding for high-definition image . Quick-release design . Extremely light and; robust The filter has a hard coating that protects the lens and sensors by preventing UV light from entering the camera. It blocks out blue light which prevents images from looking bluish or whitish when shooting in open spaces like at sea or in large fields. Specification Material Aluminium Optical Glass . Weight 1.8g . Dimensions 2.9 x 2.35 x 0.4cm