Promax Professioanl UV 37mm Filter Adapter, Glass UV Filter, Protective Cap for Gopro Hero 4, 3+, 3 (Black) + Premium High-Quality Microfiber Cleaning Cloth Fits all Gopro Hero 4, 3 and 3+ Model,Material:Glass ,Aluminum Alloy. Allows you to use other any 37mm ND, Polarized, Colored, Close up filter and lens With this filter,colours become brighter and clearer and the contrast shall be strengthened. Can limits the reflection from non-metal surface such as water and glass windows Package includes 37mm Adapter + UV filter + Cap + Premium High-Quality Cleaning Cloth