ND FILTER Reduces the amount of light entering the lens, thus decreasing the camera shutter speed. Useful for situations where motion blur needs to be created (rivers, waterfalls, moving people) or large apertures must be used with flash to avoid overexposure. Enables slow shutter speeds to be used to record movement in subjects such as waterfalls, providing a silky smooth effect to flowing water. Multiple layer nanometer coating Reduction of reflection Scratch Resistant Nanometer Coating Enables slow shutter speeds to be used to record movement in subjects such as waterfalls, providing a silky smooth effect to flowing water.    1 YEAR WARRANTY