The Seiko W650-4120 is a watch model based on the W650 movement.
Parts List
| SA0P15L20A | crystal - crystal |
| 0F300BED1 | case back gasket - case back gasket |
| 86640030 | crystal gasket - plastic gasket for crystal |
| 80633110 | pusher - button |
| HC6Z01PMS0 | pusher - button |
| 80633134 | pusher - button |
| 6A40NZ | band - band |
| W6504120SLA | others - case |
| T160BS | others - push pin |
| AD006BA11 | others - crown and stem gasket |
| 81350760 | others - button spring (front) |
| 81518099 | others - case back screw |
| 81351639 | others - button spring |
| 83200211 | others - button spring clip |