The Seiko Y131-6540 is a watch model based on the Y131 movement.
Parts List
| 240W58LN01 | crystal |
| 35MR6NS1 | crown |
| 35MR6NF1 | crown |
| FE248BC12 | case back gasket |
| 86576525 | crystal gasket - plastic gasket for crystal |
| 015LH | band - resin band |
| 017LH | band - resin band |
| 81605129 | band - bracelet fixing pin |
| 0354786 | others - winding stem |
| AD006BA12 | others - crown gasket |