UV Protector filter - Protects your camera lens from dust, moisture, scratches and fingerprints. Provides correction for Ultraviolet (UV) light which can register on film and videotape as a bluish cast and can obscure distant details. Can be left on the lens at all times. CPL Circular Polarizer filter - Removes unwanted reflections from non-metallic surfaces such as water or glass. - Increases color saturation, creating deep, rich scenic images. Adds contrast to blue skies and water shots. - Ideal for outdoor photography; minimizes haze. Filter can be rotated to determine the amount of reflection to be removed. FLD Fluorescent Correcting filter - Corrects green cast that appears when shooting under general purpose fluorescent lighting. - Dramatically increases color saturation of subjects under natural light. Construction and compatibility - These filters are manufactured from high quality solid optical glass. Each individual filter is heat treated to avoid any rare movement or distortion. - The rings are double-threaded, so you can stack filters as needed, and you can even put your lens cap on over the filters.