52mm Round Circle UV Lens Filter for GoPro HERO4 3+ 1. Made of glass and aluminum alloy material, durable to use 2. Need a filter adapter to install onto your action camera 3. Protects lens from dust, moisture, scratches, and breakage 4. With the influence from UV light. the outdoor photos look hazy. 5. The UV filters are suitable for both black and color films under bright sunshine. Which could be used to limit UV light and also as lens protector 6. UV filters are used to reduce haziness created by ultraviolet light, to which photographic film and sensors are sensitive, but not the human eye. A UV filter passes all or most of the visual spectrum, and blocks ultraviolet radiation. (Most spectral manipulation filters are named for the radiation they pass; green and infrared filters pass their named colors, but a UV filter blocks UV.) It can be left on the lens for nearly all shots: UV filters are often used mainly for lens protection in the same way as clear filters.