What does a MRC CPL Filter do? SmallRig 77mm is a double-sided multi-film polarizer designed to reduce reflections from non-metallic surfaces such as water and glass, increase saturation while retaining vivid color of photographs or videos. | 【SCHOTT B270 Optical Glass Filter】SmallRig prides itself in its filter material, unlike other normal filters, we used SCHOTT B270 Glass from Germany, which cost more but could achieve a better photo effects without damaging image quality due to its high-transmission polariser glass. Part of their unique quality is the slightly blue colour cast they feature. This cast is added to the filter intentionally in order to reduce the problem of infrared light pollution | 【18-Layers Coating on Both Side】the circular polarizer filter is coated on both sides with 18 films to increase light transmission and reduce reflections. These coatings are water-resistant, toughened to prevent stain and easy to clean and care for, which is perfect for long exposure photography (landscape/architectural photography) | 【77mm Filter Tray】The thread of the filter is made from aircraft-grade aluminium alloy, is CNC machined, laser engraved and anodized for long-term use without wear and tear. Suitable for quickly removing and attaching when using. | 【Easy To Storage】Extremely lightweight and compact, the CPL filter is perfect for transportation. A plastic storage box is for you to storage the carry the filter with you without damaging it