The Seiko W401-5050 is a watch model based on the W401 movement.
Parts List
| ES3W39LN00 | crystal |
| 010110B01 | case back gasket |
| 86566550 | case back gasket - plastic gasket for case back |
| 86174400 | crystal gasket - plastic gasket for crystal |
| 80607559 | pusher - button |
| 80607579 | pusher - button |
| GA75D | band - band |
| QA91A | band - metal band |
| W401505062D | others - case |
| W401505062E | others - case |
| A180CS | others - push pin |
Other models with the same movement
| W401-4010 |
| W401-4020 |
| W401-4040 |
| W401-4050 |
| W401-4070 |
| W401-4110 |
| W401-4130 |
| W401-413A |
| W401-4140 |
| W401-4150 |
| W401-4160 |
| W401-4180 |
| W401-5010 |
| W401-5070 |
| W401-5080 |
| W401-5110 |
| W401-5120 |
| W401-5130 |
| W401-5170 |
| W401-5180 |