Vector Optics Predator 1x28x20 Reflexible Sight Nice Streamline, 4 MOA Dot Size 21mm Weaver Base, Compact Size Light and Compact, Fancy Streamline, Fit for Real Fire Caliber and Ammunition and 5 Levels Red Dot Brightness Magnification 1.0x Tubeless Sight Window Lens Size 28x20mm Exit Pupil 22-25mm Length 60mm (2.4 inch) Width 33mm (1.3 inch) Weight (net) 100g (3.5 ounce) Eye Relief Free Field of View (M@100 Meters) 15.7 Optics Coating Multi Coated Reticle 5 Levels Red Dot Parallax 2-2.5' at 50 meters Elevation Range ±20MOA Windage Range ±20MOA Battery Type CR2032 x1 Shock proof, Rain Proof and Fog Proof High quality aluminum alloy in durable black matte finish Right and up screws are for the adjustment of windage and elevation with reticle lock feature Integrated 21mm weaver mount