The Seiko 7731-7020 is a watch model based on the 7731 movement.
Parts List
| 280A02JN02 | crystal - crystal (inorganic) |
| 280N41JN00 | crystal - crystal |
| 30N59NA5 | crown - crown |
| 0G2700B01 | case back gasket - case back gasket |
| 0G2750B01 | case back gasket - case back gasket |
| LK57B | band - band |
| 12P63C3M | others - minute hand |
| 773162 | others - machine code |
| 77317030XS19 | others - dial |
| A180BS | others - push pin |
| DZ0040B01 | others - crown and stem gasket |
| 12P03CHH | others - hour hand |
| 82707130 | others - case ring |
| 7731702025A | others - case |
| 12SC31VG | others - second hand |
| 12P63CHM | others - minute hand |