These professional quality filters are made in Japan using precision optical glass that is carefully smelted & blended to yield perfect optical results. Hoya has applied the same care & precision to the multi-coating process, using an enhanced Super Multi-Coating (IS-HMC) formula to greatly reduce or eliminate reflections off the surface of the glass. These coating are overlaid with a clear water & stain resistant coating that is easy to clean. This makes for easier care & handling of the filter in the field. All coating layers are applied in a furnace to bond the coating to the glass. All Hoya REVO filters have very low-profile aluminium filter frames to house the glass & keep it perfectly parallel to the plane of the CCD or COS sensor while providing enough rigidity to hold up to years of use. The low-profile frame also makes the filters compatible with a wide array of super & ultra wide-angle lenses. Hoya REVO series filters are available in sizes from 37mm to 82mm.