The Seiko 4N20-0380 is a watch model based on the 4N20 movement.
Parts List
| 185A01SN02 | crystal |
| 30M57NA1 | crown - crown |
| 30M57NS1 | crown - crown |
| 0H1700B01 | case back gasket - bezel gasket |
| AC004BA11 | case back gasket - crown and stem gasket |
| DZ18B | band - metal band |
| DZ19B | band - metal band |
| 06Y11JGH | others - hour hand |
| 0351155 | others - winding stem |
| 81181459 | others - bracelet fixing pipe |
| 81606899 | others - bracelet fixing pin |
| 82832995 | others - case ring |
| 4N200380 | others - case back |
| 4N20038026 | others - case |
| 4N2003802E | others - case |
| 4N200650XA15 | others - dial |
| 4N200650XA25 | others - dial |
| 4N2061 | others - machine code |
| 89942935 | others - back plate |
| 06Y11JGM | others - minute hand |
| 06Y11JSH | others - hour hand |
| 06Y11JSM | others - minute hand |