The Seiko Y131-5440 is a watch model based on the Y131 movement.
Parts List
| RE5N66GM01 | crystal - crystal (inorganic) |
| RE5N66GM02 | crystal - crystal (inorganic) |
| 35M98NF1 | crown |
| 0A2600B01 | case back gasket |
| 0G0055B01 | case back gasket - crown and stem gasket |
| 164MZ | band - metal band |
| 166MZ | band - metal band |
| A160BS | others - push pin |
| 0354786 | others - winding stem |