B+W 72mm XS-Pro Kaesemann Circular Polarizer with Multi-Resistant Nano Coating This filter uses our XS-Pro Digital mount which is especially suited for DSLRs with wide angle and zoom lenses. It has a front thread for additional accessories. All XS-Pro Digital mounts are made of brass and are matte black to prevent reflections. MRC nano has an improved outer (8th) layer over regular MRC. The nanotechnology based characteristic (lotus effect) produces a better beading effect with water making the cleaning of this filter even simpler and faster than ever before. Manufactured from Water-White Schott Glass