The frame is made of brass material, the classic design and Cnc integral molding are both rigid and flexible, and the installation is smooth and durable ultra-thin design, 0.01mm processing accuracy, the frame is highly fitted and the lens is fixed, and it is installed on wide-angle and telephoto lenses without darkening Angle produced.The frame adopts self-locking technology, 1-5 gears for 8K video shooting dimming adjustment, precise gear position. At the same time, the Cpl filter is combined to realize the 2-in-1 function. The lens uses KandF Concept's exclusive coating technology, and the reflectivity as low as 0.15% ensures ultra-high light transmittance, reduces the glare and ghost that may occur when the filter is installed on the lens, and has almost no impact on the original performance of the lens.Double-sided 36-layer nano-coating, super waterproof, anti-fouling, anti-scratch coating, providing your filter with excellent durability and easy cleaning. Each filter has a unique identification code the storage bag is made of genuine leather and is purely handmade. KandF Concept is specially designed for photographers..