III. Key Features: Double-sided multi-layer nano-coating, with high-accuracy color reproduction Made of high-clarity optical glass from Germany, with less color cast Waterproof, oil-resistant and anti-scratch Compatible with 4 x 5.65" matte box system IV. Description SmallRig 4 x 5.65" ND2.1（7 Stops）Filter 4228 is one of the CINE ND filters designed for professional photographers. It features 0.78% light transmittance, with seven stops of light extinction, and optical glass, precisely ground and polished for use with a 4 x 5.65" filter tray or matte box. Made of high-clarity, high-transmission B270 optical glass from Germany, this filter is coated on both sides with multilayer nano-coating to ensure high-accuracy color reproduction. These coatings are mildew-proof, waterproof, oil.
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