The Seiko 1F21-0B40 is a watch model based on the 1F21 movement.
Parts List
| 205W20SV02 | crystal |
| 30M58NA1 | crown - crown |
| 0A2000N01 | case back gasket |
| B5591 | band - metal band |
| 06T04NAM | others - minute hand |
| 81606439 | others - bracelet fixing pin |
| 81180229 | others - bracelet fixing pipe |
| 1F210B40 | others - case back |
| 1F210B4075 | others - case |
| 1F210B40XF | others - case |
| 1F210C00XS14 | others - dial |
| 1F219 | others - machine code |
| 82821680 | others - case ring |
| 0351807 | others - winding stem |
| EZ0035B01 | others - crown and stem gasket |
| 07T04N1H | others - hour hand |
| 06T04NBM | others - minute hand |
| 08SC22D1 | others - second hand |
| 07T04NCH | others - hour hand |