The Seiko 4N21-5440 is a watch model based on the 4N21 movement.
Parts List
| SA2A99SN02 | crystal - crystal |
| 6M40B7SNW0 | crown - crown |
| 0F160BA1S | case back gasket - case back gasket |
| D159AQ | band - band |
| 3BA075F1BA6 | others - second hand |
| 3BA075F1BNS | others - second hand |
| 1BA040A1BAK | others - hour hand |
| 2BA060A1BAK | others - minute hand |
| 2BA060A1BNS | others - minute hand |
| 1BA040A1BNS | others - hour hand |
| 0351155 | others - winding stem |
| 81606439 | others - bracelet fixing pin |
| 81190875 | others - bracelet fixing pipe |
| 81604779 | others - bracelet fixing pin |
| 4N21544079A | others - case |
| 82839370 | others - case ring |
| 4N215440 | others - case back |
| 4N212580XS13 | others - dial |
| 4N212590XZ13 | others - dial |
| 4N2165 | others - machine code |
| 89942935 | others - back plate |
| DZ0040B01 | others - crown and stem gasket |