The Seiko Y131-5640 is a watch model based on the Y131 movement.
Parts List
| ESFN60LN01 | crystal |
| 35M98NS1 | crown |
| 35M98NF1 | crown |
| 0A2600B01 | case back gasket |
| 0G0055B01 | case back gasket - crown and stem gasket |
| GL88BA | band - leather band |
| GL97B | band - leather band |
| A180BS | others - push pin |
| 0354786 | others - winding stem |
| 09C44NAH | others - hour hand |
| 09C44NSH | others - hour hand |
| 13SC04A2 | others - second hand |
| 10C26NSM | others - minute hand |
| 10C26NGM | others - minute hand |