The Seiko 2P21-0B00 is a watch model based on the 2P21 movement.
Parts List
| 190W24SN01 | crystal |
| 30MA2NA1 | crown - crown |
| 30MA2NS1 | crown - crown |
| 0A1800N01 | case back gasket |
| DK36C | band - leather band |
| DK39C | band - leather band |
| DK40C | band - leather band |
| DK41C | band - leather band |
| 07SC02NG | others - second hand |
| 07SC02NS | others - second hand |
| 07SC02AB | others - second hand |
| 82801760 | others - case ring |
| 2P210B00 | others - case back |
| 2P210B0075 | others - case |
| 2P210B007E | others - case |
| 2P210F10X999 | others - dial |
| 2P210F20XG19 | others - dial |
| 2P210F30XS19 | others - dial |
| 2P219 | others - machine code |
| A120AS | others - push pin |
| 0351236 | others - winding stem |
| EZ0035B01 | others - crown and stem gasket |
| 07TB8AGH | others - hour hand |
| 07TB8AGM | others - minute hand |
| 07T30NAH | others - hour hand |
| 07T30NAM | others - minute hand |
| 07TB8ASH | others - hour hand |
| 07TB8ASM | others - minute hand |
Caliber 2P21
