The Seiko 3F31-0A90 is a watch model based on the 3F31 movement.
Parts List
| 180W30SN01 | crystal |
| 35MF6NA1 | crown |
| 0F180NAAS | case back gasket - case back gasket |
| 86580060 | crystal gasket - plastic gasket for crystal |
| HB11B | band - metal band |
| 07SC06DG | others - second hand |
| 81180229 | others - bracelet fixing pipe |
| 81611339 | others - bracelet fixing pin |
| 0354735 | others - winding stem |
| 82833700 | others - case ring |
| 3F310A90 | others - case back |
| 3F310A9098 | others - case |
| 3F310A90X914 | others - dial |
| 3F311 | others - machine code |
| 87020760 | others - back plate |
| EA0040B0A | others - crown and stem gasket |
| 1BF050L0BCC | others - hour hand |
| 2AF075L0BCC | others - minute hand |