Featuring advanced light-sensing capabilities, the Trijicon RMR HD Red Dot Sight knows just how bright your reticle should be for given light conditions. The RMR HD's forward-facing sensor measures light at the target, eliminating reticle "wash-out" when aiming into bright light and "bloom" when the target is dim. Naturally, you can also opt for one of the nine preset daylight brightness levels, including three for night-vision gear and one super-bright. An index ridge on top of the sight helps with sight picture acquisition from atypical positions. Zeroing is easy, even when wearing gloves, with the tactile and audible elevation and windage adjusters, upgraded from previous models. The sight features the same toughness you've come to expect from Trijicon red dots: aluminum construction, force-dispersing body shape, and waterproof performance as deep as 66 feet.