The Ruger SR series was produced from 2007 to 2019, in the forms of the Ruger SR9, the Ruger SR40, and the Ruger SR45, and in both compact and full sized variations. The SR pistols were designed to replace the P-series, by being modernized with a striker fired mechanism and a polymer frame.
Notable features of the SR series include a red loaded chamber indicator on the top of the slide, and a frame mounted thumb safety. The polymer frame is reinforced with fiberglass for superior durability. It also came with a firing pin indicator that prevented the weapon from being fired if dropped.