The Seiko 5P31-5A50 is a watch model based on the 5P31 movement.
Parts List
| ES9W20HM01 | crystal |
| 35MA8NA1 | crown |
| 0A2400N01 | case back gasket - case back gasket |
| 0A2400NO | case back gasket |
| 86574840 | crystal gasket - plastic gasket for crystal |
| 86574841 | crystal gasket - plastic gasket for crystal |
| B1449C | band - metal band |
| B1449C-LKG | band - link |
| B1449D | band - metal band |
| B1449D-LKG | band - link |
| B1449D-BK4G | clasp - clasp |
| B1449C-BK4G | clasp - clasp |
| 08T32ZAH | hand - hour hand |
| 08T32ZAM | hand - minute hand |
| 09T04N1H | others - hour hand |
| 5P315A50SA | others - case |
| 5P315A50WE | others - case |
| 5P315A50XN14 | others - dial |
| 5P315A60XN14 | others - dial |
| 5P319 | others - machine code |
| 82802500 | others - case ring |
| 81180229 | others - bracelet fixing pipe |
| 81604259 | others - bracelet fixing pin |
| 0351670 | others - winding stem |
| 2BA090A0BNG | others - minute hand |
| 13SC04A2 | others - second hand |
| 0Z0060B01 | others - crown and stem gasket |
| 09T18NGM | others - minute hand |