The Seiko 5B21-0AC0 is a watch model based on the 5B21 movement.
Parts List
| D257AB | band - band |
| D257AB-LK00 | band - link |
| D257AB-BK00 | clasp - clasp |
| D257AB-BKLK-12H | clasp - parts for buckle/clasp |
| D257AB-BKLK-6H | clasp - parts for buckle/clasp |
| D257AB-BKPP | others - spring bar for buckle/clasp |
| D257AB-LK01 | others - half adjust link |
| D257AB-LKPN | others - pin for link |
| 81610189 | others - bracelet fixing pin |
| 81180249 | others - bracelet fixing pipe |
Other models with the same movement
| 5B21-0AA0 |
| 5B21-0AB0 |
| 5B21-0AD0 |
| 5B21-0AE0 |
| 5B21-0AF0 |