Marumi DHG Circular Polarising Filter 43mm is well suited to use with wide-angle lenses and ideal to enhance picture quality by blocking harmful reflected light. The Sigma filter is an essential accessory for outdoor photography and fits to selected lenses with a 43mm filter thread. The filter protect front lens surface from dust, scratches, dirt and fingerprints. The polarizer helps make a blue sky more bluer as well as making clouds stand out. The effect can be seen through the viewfinder and changed by rotating the filter. The Ultra-low reflective coating and smooth frame helps minimize reflection off internal CCD and CMOS sensors. The filter is equipped with improved antireflection coatings and the glass edges are blackened to avoid internal reflections. The filter removes unwanted reflections from non-metallic surfaces such as water or glass and also saturates colors providing better contrast.