The HD Mk II coatings are among the toughest, most scratch and dirt resistant coatings offered by any manufacturer. The highly transparent polarizing film has 25% better light transmission than the standard polarizing film used in current photographic filters. This means that almost half a stop more light enters the lens while achieving the same polarizing effect, maintaining the color balance of a standard circular polarizer while improving contrast and clarity. With the Hoya HD Mk II CIR-PL filter, you can create unique effects in your photo that are not possible with post-processing software. One such effect is controlling light reflections on glass or water surfaces. The filter allows you to control the light waves entering your lens by filtering all polarized light. This allows you to see under water surfaces, for example. In addition to being ultra-hard and smooth, the HD Mk II coating has excellent water and oil repellent properties that make filter maintenance easy and stress-free. The ultra-thin frame is compatible with wide-angle lenses. The glass was assembled via high-pressure molding technology.