Item Type: UHC Light Pollution Filter Material: Aluminum Alloy, Optical Glass Weight: Approx. 51g / 1.8oz Package List 1 x Filter 1 x Storage Box 1Light Damage Suppression Filter: It has a significant effect on eliminating harmful urban light, especially artificial light such as street lights, background lights, landscape lights, and skylight. This is a high contrast filter that enhances the contrast between nebula and starlist sky, reproducing rich nebula details. 2Optical Glass Substrate and Coating: Due to the fact that the filter belongs to interference filters, the displayed colors vary at different angles, ensuring that the film layer is resistant to high temperature, corrosion, and is not easy to peel off, the coating is uniformly coated. 3Widely Used: 2 inch UHC light pollution reduction filter for telescope can serve as a permanent lens protector and can be used for digital imaging of digital SLR cameras, CCD cameras, and modified network cameras or telescopes. 42 Inch Filter Thread: A standard 2 inch filter frame, suitable for 2 inch eyepieces and other accessories, with a 2 inch thread at the bottom of the eyepiece. 5Portable Storage: Comes with a plastic box, the 2 inch ultra high contrast UHC light pollution reduction filter can be kept safe and clean when not in use.