The Seiko W820-4040 is a watch model based on the W820 movement.
Parts List
| 300P03LN03 | crystal - crystal (inorganic) |
| FE328BAA3 | case back gasket - case back gasket |
| 86620275 | crystal gasket - plastic gasket for crystal |
| 80710919 | pusher - button |
| F100GG | band - band |
| 82825150 | others - case ring |
| W8204040SWA | others - case |
| W8204040 | others - case back |
| A180BS | others - push pin |
| 83200273 | others - button spring clip |
| AD006BA11 | others - crown and stem gasket |
| 81351639 | others - button spring |
Other models with the same movement
| W820-4000 |
| W820-4004 |
| W820-4010 |
| W820-4020 |
| W820-4030 |
| W820-4050 |