RainbowImaging 49mm Pro 1D PRO1-D Supe Slim CPL Circular PL filter (Multi-Coated) Ultra thin 1mm glass ncreases colour saturation, darken blue skies so white clouds stand out and eliminate reflections from non-metallic surfaces like glass or water. Equipped with black rimmed glass to reduce the chance of light reflecting off the edge. Low Profile Frame Ultra thin filter frames (3MM) to help avoid vignetting on super wide angle lenses are also designed to hold. Equipped with a straight knurling edge for non-slip, easy attachment and removal.