Federkit WOLFF SIG MAINSPRING KIT
Three, reduced power springs for tuning and smoothing felt trigger pull. Fits the newer P-220, P-226 and P-229Õs that use a short mainspring with a plastic, hammer spring base insert. Contains 1 each of 17, 18, and 19 lb., reduced power, mainsprings. P-220 factory spring is 22 lb. P-226 and P-229 factory spring is 24 lb.