Specially selected replacement springs to greatly improve functioning AND reduce trigger pull form the basis of a top-quality 1911 tuning job. 5 Wolff coil springs plus a factory-style, 3-leaf sear spring. Includes: Variable Power Recoil Spring which functions with a wider range of ammo than single power springs; Hammer Spring which lightens trigger pull; Extra Power Firing Pin Spring; New Magazine Catch; Series 80 Firing Pin Safety Block Spring; Plunger Tube Springs, plus the Sear Spring. Three kits - each with a different strength recoil spring. GM-454 for the Colt Combat Commander - Includes 1 each factory standard weight, 18 lb., variable power recoil spring and 23 lb. hammer spring plus, (1) 19 lb. RP hammer spring and (1) XP firing pin spring.