The Seiko 4N21-0410 is a watch model based on the 4N21 movement.
Parts List
| 170P17SN03 | crystal - crystal |
| 6K30A1SNG0 | crown |
| 0F155BAA3 | case back gasket - case back gasket |
| AC004BAA1 | case back gasket - crown and stem gasket |
| 86561171 | crystal gasket |
| ZA40A | band - metal band |
| ZA41A | band - band |
| 07T47DGH | others - hour hand |
| 07T47DGM | others - minute hand |
| 3BA075F1BNG | others - second hand |
| 0351155 | others - winding stem |
| 81606439 | others - bracelet fixing pin |
| 81180249 | others - bracelet fixing pipe |
| 81607559 | others - bracelet fixing pin |
| 82840910 | others - case ring |
| 4N2104107H | others - case |
| 4N210410 | others - case back |
| 4N21041079 | others - case |
| 4N210840XS19 | others - dial |
| 4N210850XS14 | others - dial |
| 4N211650XS14 | others - dial |
| 4N2164 | others - machine code |
| 1BH042A1BNG | others - hour hand |
| 2BH065A1BNG | others - minute hand |