Zomei&reg; Ultra Slim HD 18 Layer Super Multi-Coated SCHOTT Glass PRO Fader Variable Density Neutral Gray ND X Lens Filter - 52mm 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. With Zomei Variable Density Neutral Gray filters, users can select the intensity from ND2 (1 f-stop) to ND400 (8+ f-stops) by rotating the front ring. 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 Environ Ment Protection-ROHS(Restrictions on Hazardous Substances).