P10G18 - Spring, Recoil, Govt., 18 1/2#; P26 - Extra Power Firing Pin Spring; P27 - Reduced Power Hammer Spring 18#; R15A - Mag Catch Spring; R29 - Sear Spring; R33PS - Plunger Tube Spring; For a full-size, 5" 1911 contains every spring needed to complete or upgrade your pistol; Heat treated music wire springs are the finest quality coil springs; Extra Power recoil springs are rated for standard velocity and high-velocity loads and a reduced power hammer spring improves your trigger pull and reduces the force required to cycle the slide; Stainless Finish