Feature Maybe the Lightest Pistol Red Dot Sight in the World Only 12.4g 0.44oz Weight Engineering Polymer Housing in Rug Construction Designed for Real Firearms Standard Window Size 16x22mm 0.6x0.9", Automatic Light Sensor, MGT Footprint 50,000 Hours for Weakest Visible Dot, IPX4 Water Resistant, w/ Weaver Mount Specification Magnification: N/A Window Lens Size: 16x22 mm Parallax: Free (45 MOA Windage Adjustment Range: >45 MOA Footprint: MGT (RMSc) Mounting Rail: Weaver Illumination Setting: N/A Battery Type: CR2032 (not include) Battery Life: Up to 50,000 hours Battery Placement: N/A Waterproof: IPX4 Shockproof: 1000 G Working Temperature: -20~+ 55 AdegC Housing Material: Polymer Mount Material: 6061-T6 Aluminum Alloy Finish: Matte Black Weight (Net): 12.4 g / 0.44 oz Items in the Package: Retail Package, Weaver Mount, Rubber Lens Cover, Hex Keys and Cleaning Cloth, etc Video Size