Warm Circular Polarizer Glass Filter - Light rays which are reflected become polarized. Polarizing filters are used to select which light rays enter your camera lens. They can remove unwanted reflections from non-metallic surfaces such as water or glass and also saturate colors providing better contrast. The effect can be seen through the viewfinder and changed by rotating the filter.
NOTE: Circular polarizers are specifically designed for use with auto-focus SLR cameras (They will also work on manual systems without problems). Linear polarizers are used with most video and manual focus photo cameras. They are not recommended for auto-focus SLR cameras