HATTORY-SEIKO 7903A Exploded diagram Brand HATTORY-SEIKO Caliber 7903A Size Function Version Hands Stem 354-791 Stem (subs.) Stem (2 pce) Balance staff Balance staff (subs.) Mainspring (subs.) Mainspring (subs.) Battery Watchparts Part NocaliberdescriptionoriginalArtno.250= 2906Hour wheel271-7119840271711401Winding stem354-7919840354791