The HS507K is an open reflex optical sight designed for concealed carry pistol applications. Features include Holosun's Super LED with up to 50k hours battery life, Multi-Reticle System, Shake Awake, and Lock Mode. Features: Reticle: 2 MOA Dot & 32 MOA Circle Light Wavelength: 540nm Reticle Color: Red Parallax Free: Yes Unlimited Eye Relief: Yes Magnification: 1x Multi-Coatings: Yes Power Source: Battery Battery Type: CR1632 Battery Life (Hours): 50000 Brightness Setting: 10 DL&2 NV Housing Material: 7075 T6 Aluminum Surface Finish: Anodize Adjustment per Click: 1 MOA W&E Travel Range: A 50 MOA Window Size: 0.58x0.77 Dimension (in): 1.6x0.98x0.95 Weight (oz): 1 Storage Temperature: -40?~70? Working Temperature: -30?~60? Submersion: IP67 Vibration: 5000G