3-In-1 Tuning Choices
Various weights of reduced power hammer springs in one kit help you precisely tune your semi-auto pistol for the smoothest double- and/or single-action pull and proper function. KIT #26582 S&W 469/669, 6904/6906, 3913/3914 (Incl. L/S), 4516/4516-1, 1066/1076 - Contains 1 each 17 lb., 18 lb. and 20 lb. hammer springs. Factory spring is 20 lbs.
Big Book Catalog, Issue:66, Page:218