The Seiko 1F21-5D20 is a watch model based on the 1F21 movement.
Parts List
| RE1A96SR02 | crystal - crystal |
| 40MG6NS1 | crown - crown |
| 0F180NA1S | case back gasket - case back gasket |
| D0T9CZ | band - band |
| 3BA075F0BNG | others - second hand |
| 1BG035L0BDG | others - hour hand |
| 2BG050L0BDG | others - minute hand |
| A120BS | others - push pin (for lb) |
| 1F211H70XS2Z | others - dial |
| 1F215 | others - machine code |
| 0351807 | others - winding stem |
| 82837920 | others - case ring |
| 1F215D207L | others - case |
| 1F215D20 | others - case back |
| EZ0035B01 | others - crown and stem gasket |