X4 CPL 67mm Circular Polarizer Filter - Schott B270 - MRC16 - Nano Coating - Weather Sealed - 25 Year Support by Breakthrough Photography

The X4 CPL features SCHOTT Superwhite B270 optical glass, which is an ultra clear crown glass. It is produced by melting high purity raw materials and then made using the continuous draw process. The result is excellent transmission in the ultraviolet, visible, and infrared spectrums, and a high surface quality that accepts our state-of-the-art MRC and nanotec coatings exceptionally well.