The Holosun® HS506 Red Dot Sight is a 30mm sight, specifically engineered for rifle and carbine applications. The hard coat anodized 6061 T6 aluminum housing easily withstands heavy recoil, while the multilayer reflective glass lenses deflect stray light away from your eye for exceptional clarity and reduced eye fatigue. The proprietary Multi-Reticle System allows you to choose your favored reticle (2 MOA dot or 2 MOA dot with 65 MOA circle) for enhanced reliability, while 12 brightness settings (10 daylight; 2 night vision) deliver exceptional clarity in any lighting. Shake Awake™ technology automatically activates the red dot when it detects motion for instant, hands-free activation, and flip-back lens covers offer superior protection from bumps, scratches, and abrasions. Operating on a single CR2032 battery (included), the HS506 Red Dot offers an impressive 50,000-hour battery life (lowest setting). IP67 waterproof.