The Seiko 4N21-0800 is a watch model based on the 4N21 movement.
Parts List
| 175P01HN03 | crystal |
| 6M30B5NNG1 | crown - crown |
| 0F150BAA5 | case back gasket - case back gasket |
| 86173361 | crystal gasket |
| RM05A | band - metal band |
| RM06A | band - metal band |
| 1BC047A1BNG | others - hour hand |
| 2BC070A1BNG | others - minute hand |
| 3BA075F1BNG | others - second hand |
| DZ0040B01 | others - crown and stem gasket |
| 0351155 | others - winding stem |
| 82841030 | others - case ring |
| 4N210800 | others - case back |
| 4N21080075A | others - case |
| 4N2108007NA | others - case |
| 4N211530XG14 | others - dial |
| 4N211540XS14 | others - dial |
| 4N2164 | others - machine code |
| A100AS | others - push pin |
| 1BA047A1BNG | others - hour hand |
| 2BA070A1BNG | others - minute hand |