HATTORY-SEIKO 1520A Exploded diagram BrandHATTORY-SEIKOCaliber1520ASizeFunctionVersionHandsStem351-152Stem (subs.)Stem (2 pce)Balance staff315-120Balance staff (subs.)Mainspring (subs.)Mainspring (subs.)BatteryWatchpartsPart NocaliberdescriptionoriginalArtno.401BWinding stem9840351152