UTAC Sensor Tactical Micro Compact Mini Open Reflex Red Dot Sight with Automatic Reticle Brightness Control for Pistol / Rifle / Shotgun No Switch, Automatic Reticle Brightness Control Lenses are precision ground and polished to exacting geometries to virtually eliminate parallax and to provide a very clear, crisp sight picture Fully windage and elevation adjustable and lockable; Unlimited Eye Relief Waterproof/Shock/Fog Resistant; 5 MOASettings Powered by a lithium CR2032 battery (Included)