The Seiko 5P31-5B90 is a watch model based on the 5P31 movement.
Parts List
| SA9W18SN01 | crystal |
| 40M78NS1 | crown - crown |
| 0A2500N0A | case back gasket - case back gasket |
| 86580660 | crystal gasket |
| YA41A | band - metal band |
| 0351670 | others - winding stem |
| 5P315B90 | others - case back |
| 5P315B9099 | others - case |
| 5P315C80XS19 | others - dial |
| 5P319 | others - machine code |
| 82802500 | others - case ring |
| A160BS | others - push pin |
| 08TB2FSH | others - hour hand |
| 13SC04ES | others - second hand |
| 0Z0060B01 | others - crown and stem gasket |
| 08TA0ASM | others - minute hand |