Smith & Wesson Mainspring Stirrup 38-3, 49-3, 60-9, 317, 331, 332, 337, 337PD, 340, 340PD, 342, 342PD, 351PD, 360, 360PD, 431PD, 432PD, 442, 637-1, 638-2, 642 (for use with Mim Hammer Only)

This Smith & Wesson Mainspring Stirrup is a replacement for the original, if it has become lost or damaged. Factory replacement parts are manufactured to the exact same specifications and tolerances and use the same manufacturing materials as the original parts. Some parts may require installation by a qualified gunsmith.