The Seiko 4N20-0310 is a watch model based on the 4N20 movement.
Parts List
| 180A02SV0A | crystal - crystal |
| 30M57NS1 | crown - crown |
| 0H1700B01 | case back gasket - bezel gasket |
| AC004BA11 | case back gasket - crown and stem gasket |
| MK31E | band - leather band |
| 0351155 | others - winding stem |
| 06Y01DGH | others - hour hand |
| 82841070 | others - case ring |
| 4N2003102E | others - case |
| 4N200460XS15 | others - dial |
| 4N2061 | others - machine code |
| A100AS | others - push pin |
| 06Y01DGM | others - minute hand |