The Seiko W309-4200 is a watch model based on the W309 movement.
Parts List
| SA9W56LM01 | crystal |
| SA9W56LM02 | crystal |
| EA0091B0A | case back gasket |
| 86575580 | crystal gasket |
| 0Z2900B01 | bezel gasket - dichtung |
| 80615580 | pusher |
| GL87B | band - leather band |
| A170CS | others - push pin |