Smith & Wesson Center Pin Spring

FITS: 36, .38; 37, .38; 42/442, .38; 49, .38; 60, .38, .357; 317, .22; 331TI, .32 Mag; 332TI, .32 Mag; 337TI, .38; 342TI, .38; 637, .38; 638, .38; 640, .38; 640 Magnum, .357; 642, .38; 649, .38, .357; 940, 9mm