The Seiko 4N21-0580 is a watch model based on the 4N21 movement.
Parts List
| 185W39SN02 | crystal - crystal |
| 6K30A1SNG1 | crown - crown |
| 0F175BAA5 | case back gasket - case back gasket |
| 0F170BAA1 | case back gasket |
| AC004BAA1 | case back gasket - crown and stem gasket |
| 86561071 | crystal gasket |
| DA68BW | band - band |
| DA68DW | band - band |
| 3BA075F1BNG | others - second hand |
| A120BS | others - push pin (for lb) |
| 4N211120XS14 | others - dial |
| 4N212010XS14 | others - dial |
| 4N2164 | others - machine code |
| 0351155 | others - winding stem |
| 82832995 | others - case ring |
| 4N21058075 | others - case |
| 82280535 | others - bezel |
| 4N210580 | others - case back |
| 4N21058075B | others - case |
| 07T31DGH | others - hour hand |
| 07T31DGM | others - minute hand |
| 1BD050LDBDG | others - hour hand |
| 2BD072LABDG | others - minute hand |
| 185W39SN02 | crystal - crystal |
| 6K30A1SNG1 | crown - crown |
| 0F175BAA5 | case back gasket - case back gasket |
| 0F170BAA1 | case back gasket |
| AC004BAA1 | case back gasket - crown and stem gasket |
| 86561071 | crystal gasket |
| DA68BW | band - band |
| DA68DW | band - band |
| 3BA075F1BNG | others - second hand |
| A120BS | others - push pin (for lb) |
| 4N211120XS14 | others - dial |
| 4N212010XS14 | others - dial |
| 4N2164 | others - machine code |
| 0351155 | others - winding stem |
| 82832995 | others - case ring |
| 4N21058075 | others - case |
| 82280535 | others - bezel |
| 4N210580 | others - case back |
| 4N21058075B | others - case |
| 07T31DGH | others - hour hand |
| 07T31DGM | others - minute hand |
| 1BD050LDBDG | others - hour hand |
| 2BD072LABDG | others - minute hand |