The Trijicon RMR is designed to improve accuracy and precision with any firearm it is attached to. The sight is very durable because its housed in forged aluminum. The Trijicon RMR is exceedingly durable and very lightweight. It's also extremely simple to sight in with the audible clicks. It will perform under the harshest operating conditions thanks to the high-strength of the housing, forged, military-grade, aluminum that absorbs shock. The reticle is red and takes a CR2032 battery (battery life 1700hrs and the battery is included.) Simple to operate, no switches to forget to activate under stress because the sight is always on! Once the Trijicon RMR is on one firearm you will want it on all your firearms!