The Seiko 4N20-0120 is a watch model based on the 4N20 movement.
Parts List
| 200WC1SR01 | crystal |
| 30M71NH4 | crown |
| 30M71NS4 | crown |
| 0F150BAA5 | case back gasket - case back gasket |
| HB47A | band - metal band |
| HB48A | band - metal band |
| 06Y53JGH | others - hour hand |
| 0351155 | others - winding stem |
| 81182699 | others - bracelet fixing pipe |
| 81609399 | others - bracelet fixing pin |
| 82841070 | others - case ring |
| 81609579 | others - bracelet fixing pin |
| 4N200120 | others - case back |
| 4N20012061A | others - case |
| 4N20012075A | others - case |
| 4N200290XN14 | others - dial |
| 4N200290XY14 | others - dial |
| 4N2060 | others - machine code |
| DZ0040B01 | others - crown and stem gasket |
| 06Y53JGM | others - minute hand |