I have the following springs, new in the package, that fit the S&W 3904/5904 9mm series pistols:
Firing Pin Spring, extra power, set of 3.
Extractor spring, 6.5lb, extra power, set of 2.
Recoil Springs, 14, 16, 17, 18 & 20lb.
This is an "all or nothing" deal. $25.00 delivered to the lower 48. MC/VISA