This red dot uses the Trijicon RMR footprint standard. Essential info Footprint standard: Trijicon RMR footprint standard Reticle: Competition MRS [various dot/circle options] [green] Window size [height x width]: 22.1 x 27.9 mm [0.87 x 1.1"] Total dimensions [length x width x height]: 41.1 x 27.2 x 24.1 mm [1.62 x 1.07 x 0.95"] 507Comp-GR handgun sight features a large 1.1” x 0.87” objective lens for enhanced shooting performance and Holosun’s new Competition Reticle System (CRS) with Holosun’s 540nm Green Super LED and up to 50k hour battery life with a 1632 cell. CRS is an enhanced multi-reticle system with four components including a precision 2MOA dot, an 8MOA circle, 20MOA circle, and 32MOA circle with multiple combination settings to suit individual shooter preference. 507Comp-GR is made from 7075 aluminum with an industry standard footprint, and includes Shake Awake technology. OPTICAL SPECS Reticle 2 MOA Dot & 8/20/32 MOA Circle Light Wavelength 540nm Reticle Color Green Parallax Free Yes Unlimited Eye Relief Yes Magnification 1x Multi-Coatings Yes ELECTRONIC SPECS Power Source Battery Battery Type CR1632 Battery Life (Hours) 50000 Brightness Setting 8 DL & 2 NV PHYSICAL SPECS Window Size 1.1×0.87 Dimension (in) 1.8×1.3×1.3 Weight (oz) 1.7 MECHANICAL SPECS Housing Material 7075 T6 Aluminum Surface Finish Anodize Adjustment per Click 1 MOA W&E Travel Range ±30 MOA ENVIRONMENT SPECS Storage Temperature -40℃~70℃ Working Temperature -30℃~60℃ Submersion IP67 Vibration 5000G