HD110 Compact Open Reflex Red Dot Sight. This lightweight 1x reflective red dot sight is CNC machined from durable aluminum alloy, built with a large round 22mm objective lens for wide field of view and unlimited eye relief for fast two-eyes-open aiming. It features 4 reticle patterns with smooth stepless red & green dual brightness adjustment, adapting to bright sunlight and low-light dusk environments. Precision windage and elevation turrets allow easy zeroing, compatible with both 11mm and 22mm standard rails.