The Seiko 1F21-0H20 is a watch model based on the 1F21 movement.
Parts List
| 145W06SK01 | crystal |
| 25MA2NJ4 | crown |
| 0F130NA1S | case back gasket - case back gasket |
| 81180583 | band - bracelet fixing pipe |
| WJA61 | band - leather band |
| 81503029 | others - screw |
| 86503923 | others - decorative plate |
| 0351807 | others - winding stem |
| 05T42DSH | others - hour hand |
| 82821000 | others - case ring |
| 81604329 | others - bracelet fixing pin |
| 1F210H20 | others - case back |
| 1F210H2071 | others - case |
| 1F211B50XS13 | others - dial |
| 1F219 | others - machine code |
| 05T42DSM | others - minute hand |
| EZ0035B01 | others - crown and stem gasket |
| 06SC21VS | others - second hand |