Zomei Ultra Slim HD 18 Layer Super Multi-Coated Schott Glass PRO 6-Stop Neutral Density Gray ND64 Lens Filter - 100mm x 100mm Square Z-PRO Series 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. 6 Stop Exposure, No Color Cast, Top Smooth finish on The Surface. Nearly zero distortion when light go through this HD filter. With only 2.3mm thickness and made with no compromise, this ND1000 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 Environ Ment Protection-ROHS(Restrictions on Hazardous Substances).