The Seiko 4N21-0220 is a watch model based on the 4N21 movement.
Parts List
| 170A02SN02 | crystal - crystal (sapphire) |
| 30MJ7NA1 | crown - crown |
| 0F150BAA5 | case back gasket - case back gasket |
| 0H1600B01 | case back gasket - case back gasket |
| DB03B | band - band |
| DK43D | band - band |
| 07SC19XB | others - second hand |
| 07T49JBM | others - minute hand |
| 07T83JBH | others - hour hand |
| 07T83JBM | others - minute hand |
| 1BH047A1BNB | others - hour hand |
| 2BH070A1BNB | others - minute hand |
| 3BA075F1BNG | others - second hand |
| 07T73JGH | others - hour hand |
| 07T73JGM | others - minute hand |
| 3BA075F1BAB | others - second hand |
| 07SC17NG | others - second hand |
| 07SC43XB | others - second hand |
| A110BS | others - push pin (for mb) |
| 4N210580XS14 | others - dial |
| 4N210590XS19 | others - dial |
| 4N210600XS19 | others - dial |
| 4N2164 | others - machine code |
| 4N21022098 | others - case |
| 4N210220 | others - case back |
| DZ0040B01 | others - crown and stem gasket |
| 0351156 | others - winding stem |
| 82841070 | others - case ring |
| 82351251 | others - bezel |