The Seiko 4N20-5040 is a watch model based on the 4N20 movement.
Parts List
| K00W69SK01 | crystal |
| 30M57NA1 | crown - crown |
| 30M57NS1 | crown - crown |
| 0F135BAA3 | case back gasket |
| AC004BA11 | case back gasket - crown and stem gasket |
| MK54D | band - leather band |
| MK55D | band - leather band |
| T090BS | others - push pin |
| 0351155 | others - winding stem |
| 4N200140XS14 | others - dial |
| 4N200140XS24 | others - dial |
| 4N205040 | others - case back |
| 4N20504075 | others - case |
| 4N2050407E | others - case |
| 82833010 | others - case ring |
| 05Y21CGM | others - minute hand |
| 05Y21AGH | others - hour hand |
| K00W69SK01 | crystal |
| 30M57NA1 | crown - crown |
| 30M57NS1 | crown - crown |
| 0F135BAA3 | case back gasket |
| AC004BA11 | case back gasket - crown and stem gasket |
| MK54D | band - leather band |
| MK55D | band - leather band |
| T090BS | others - push pin |
| 0351155 | others - winding stem |
| 4N200140XS14 | others - dial |
| 4N200140XS24 | others - dial |
| 4N205040 | others - case back |
| 4N20504075 | others - case |
| 4N2050407E | others - case |
| 82833010 | others - case ring |
| 05Y21CGM | others - minute hand |
| 05Y21AGH | others - hour hand |