Hoya REVO Protector professional quality filters are made in Japan using precision optical glass that is carefully smelted and blended to yield perfect optical results. Hoya has applied the same care and precision to the multi-coating process, using an Improved Super Multi-coating (IS-HMC) formula to greatly reduce or eliminate reflections off the surface of the glass. These coatings are overlaid with a clear water & stain resistant coating that is easy to clean. This makes for easier care and 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 Super-Slim aluminium filter frames to avoid vignetting and make them compatible with super or ultra-wide-angle lenses.