The Seiko 7321-0420 is a watch model based on the 7321 movement.
Parts List
| 175W04JN01 | crystal |
| 30M58NA1 | crown - crown |
| 0A1800N01 | case back gasket |
| 86573941 | crystal gasket |
| DS45A | band - metal band |
| 08T04NGH | others - hour hand |
| 07T08NGM | others - minute hand |
| 07SC02NG | others - second hand |
| 0354735 | others - winding stem |
| 82731680 | others - case ring |
| 7321042075 | others - case |
| 73211830XG14 | others - dial |
| 73219 | others - machine code |
| EZ0035B01 | others - crown and stem gasket |