HD101 Blue Reflex Red Dot Sight.  This lightweight tubeless reflex optic features a large 22×33mm lens for an ultra-wide field of view, ideal for fast tracking moving targets. It comes with 4 interchangeable reticle patterns, parallax correction and unlimited eye relief for consistent quick aiming. Lockable Allen screw turrets deliver precise windage and elevation adjustment. The integrated base holds zero reliably after disassembly and remounting. Built waterproof and shockproof with low power draw for extended battery runtime.