CPL Polarizer Function: Eliminate surface reflections from non-metallic objects, increase saturation, restore true colors, make the blue sky bluer, the water more transparent, and plant colors more realistic. The CPL filter lens can enhance the saturation of the object. Add a polarizer in front of the camera lens before shooting and rotate it to the desired angle to add more saturation to the subject. This ultra-thin polarizer uses imported optical glass materials to ensure a more stable color balance of light transmittance. To prevent overexposure, the polarizer can be used as a gray filter, which can reduce the lens's light transmittance without affecting the normal color reproduction of the work. Universal clip-on design, easy to attach the lens firmly to your device. Portable and detachable, you can take pictures with your devices anytime during the trip. Lens fixed focal length: 37 millimeters