HATTORY-SEIKO 2B21 Exploded diagram Brand HATTORY-SEIKO Caliber 2B21 Size 6 3/4x8 Function Version Hands Stem 354-235 Stem (subs.) Stem (2 pce) Balance staff Balance staff (subs.) Mainspring (subs.) Mainspring (subs.) Battery MovementsArtno.brandcaliberSizehandsfunctionspecial161643HATTORY-SEIKOV238 A5 1/20.65x1.10x0.18SC