The Seiko 4N21-0010 is a watch model based on the 4N21 movement.
Parts List
| 185W55SK01 | crystal - crystal |
| 30M57NA1 | crown - crown |
| 0F150BAA5 | case back gasket - case back gasket |
| AC004BA11 | case back gasket - crown and stem gasket |
| MK52D | band - leather band |
| MK53D | band - leather band |
| 3BA075F1BNG | others - second hand |
| 07SC17NG | others - second hand |
| 1BC050A1BAA | others - hour hand |
| 0351155 | others - winding stem |
| 82832990 | others - case ring |
| 4N210010 | others - case back |
| 4N21001075 | others - case |
| 4N2100107N | others - case |
| 4N210010XS14 | others - dial |
| 4N210020XS14 | others - dial |
| 4N2164 | others - machine code |
| T090BS | others - push pin |
| 07T57AGH | others - hour hand |
| 07T57AGM | others - minute hand |
| 07T23AFM | others - minute hand |
| 2BC075A1BAA | others - minute hand |