Monstrum R05 Open 26mm Red/Green Dot Reflex Sight with Weaver/Picatinny Rail Mount The R05 is a 1x26mm open reflex sight with a compact, lightweight design fit for mounting on rifles, shotguns or even pistols Four selectable reticle patterns, illumination in red and green, and adjustable brightness intensity, for a clean sight picture regardless of lighting conditions or environment Flexible eye relief, suitable for almost any shooter or firearm Mounts easily to any Weaver/Picatinny rail Sturdy anodized aluminum construction with black matte finish