Holosun 510 1x Open Reflex Sight - The HS510C is an open reflex optical sight designed for rifle and carbine applications. Features include Holosun's Super LED with up to 50k hours battery life, Multi-Reticle System, Solar Failsafe, and Shake Awake. In the Box Absolute Cowitness QD Mount T10 L Key User Manual CR2032 Battery Lens Cloth Features MRS: Circle Dot; 2 MOA Dot; 65 MOA Circle Up to 50,000 Hours Battery Life (Setting 6) 12 Brightness Setting: 10 DL & 2 NV Compatible Convenient Tray Battery Compartment Parallax-free & Unlimited Eye Relief Housing Material - Aluminum & Titanium Hood Submersion - IP67