NUANCES Extreme filters are made of a highly resistant mineral glass, able to resist accidental fall and introducing innovative technology.A new coating process ensures an uniform density and a nano metallic alloy is applied on both side of a highly resistant tempered glass, resulting in a stunning neutrality. Nuances Extreme Center Grade ND4 allows 2 f.stops of light compensation on a linear area, for precise exposure adjustment . Round corners and 2mm thickness makes Nuances Extreme filters easier to insert in extreme conditions. COKIN recommends the use of EVO filter-Holder to ensure an efficient light-leaks protection.