SmallRig MagEase Magnetic CPL Filter Kit with Universal Filter Adapter (52mm) 4389 is a filter kit, that includes a CPL and a universal filter adapter. The CPL can eliminate reflection from non-metallic surfaces (such as lakes, windows, waterfalls, glass, buildings, etc.), thereby improving image saturation. Increased colour saturation means a bluer sky and more transparent water. It can also be used as an ND filter, reducing light by 1-2 stops. To eliminate reflection, you just need to rotate the CPL filter properly. Made of German Schott B270i HD glass, the filter features waterproof, stain-resistant, mildewproof, and scratch-resistant AR coatings, with less colour cast and a CNC-machined ultra-thin frame. No vignetting even in shooting using an ultra-wide angle lens. It can be magnetically and securely attached to the SmallRig magnetic filter adapter ring.