Zomei Circular 77mm Ultra Slim HD ND1000 18 Layer Multi-Coated Optical SCHOTT Glass 10 Stop Neutral Density Lens Filter Double Thread, 18-Layer super anti-reflection multi-coated with EVERCLEAR 5(WATER REPELLENT / ANTI-OIL / ANTI-DUST / ANTI-SOIL / SCRATCH RESISTANT) Coating Technology to withstand almost any conditions. 10 step exposure. No color cast. Top smooth finish on the surface. Nearly zero distortion when light go through this HD filter. With only 6.8mm thickness and made with no compromise, this Variable ND X Filter might be the thinnest and the best in the world. Original SCHOTT Glass from Germany, Compare B+W. All Materials Used in this filter Meet the Requirements of European Union's standards of Environment Protection-ROHS