IWC 431 Brand IWC Caliber 431 Size Function Version Hands Stem 5318 Stem (subs.) Stem (2 pce) Balance staff 27522 Balance staff (subs.) Mainspring (subs.) eigen Mainspring (subs.) Battery WatchpartsPart NocaliberdescriptionoriginalArtno.210BThird wheel94200210431401Winding stem8025318723Balance staff ST -shock-absorber80227522