The Seiko 1F21-0F90 is a watch model based on the 1F21 movement.
Parts List
| 170W08SN02 | crystal |
| 6K30A0SNG1 | crown |
| 0A1700N01 | case back gasket - case back gasket |
| MK42F | band - leather band |
| 1BB045A2BNG | others - hour hand |
| 0351807 | others - winding stem |
| 82822840 | others - case ring |
| 1F210F90 | others - case back |
| 1F210F90MA | others - case |
| 1F210J90X914 | others - dial |
| 1F210J91XS14 | others - dial |
| 1F215 | others - machine code |
| A110AS | others - push pin |
| EZ0035B01 | others - crown and stem gasket |
| 2BB065A0BNG | others - minute hand |
| 3BA080F0BNG | others - second hand |