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;