The Seiko 5P31-5A20 is a watch model based on the 5P31 movement.
Parts List
| RE5N26GN00 | crystal |
| 30MA6NA1 | crown - crown |
| 0G0055B01 | case back gasket - crown and stem gasket |
| 0H2600N01 | case back gasket - case back gasket |
| Z1314G | band - metal band |
| Z1350G | band - metal band |
| Z1351G | band - metal band |
| Z1351G-BK5G | clasp - clasp |
| Z1350G-BK5G | clasp - clasp |
| Z1314G-BK5G | clasp - clasp |
| 09T04N1H | others - hour hand |
| 09T04N1M | others - minute hand |
| 10T16NAH | others - hour hand |
| 5P315A20 | others - case back |
| 5P315A2025 | others - case |
| 5P315A30XG14 | others - dial |
| 5P315B80XG14 | others - dial |
| 5P315B90XB14 | others - dial |
| 5P315B90XG14 | others - dial |
| 5P319 | others - machine code |
| 82800200 | others - case ring |
| A160BS | others - push pin |
| 08T50ZGH | others - hour hand |
| 0351670 | others - winding stem |
| 08T50ZGM | others - minute hand |
| 13SC04A2 | others - second hand |