The Seiko 5E31-5A20 is a watch model based on the 5E31 movement.
Parts List
| ESBW30SV01 | crystal |
| ESBW30SV02 | crystal |
| 32M10NS1 | crown |
| 32M10NB1 | crown |
| 0A2700B01 | case back gasket - gasket |
| AB60A | band - metal band |
| AB61A | band - metal band |
| 09T46DCM | others - minute hand |
| 0351624 | others - winding stem |
| 81180229 | others - bracelet fixing pipe |
| 81604259 | others - bracelet fixing pin |
| 5E311 | others - machine code |
| 5E315A20 | others - case back |
| 5E315A2061 | others - case |
| 5E315A20WE | others - case |
| 5E315A20XS1Z | others - dial |
| 5E315A20XS2Z | others - dial |
| 82813800 | others - case ring |
| 87020283 | others - back plate |
| EZ0035B01 | others - crown and stem gasket |
| 10T42DCH | others - hour hand |
| 12ST12TA | others - second hand |