The Seiko 4N21-5320 is a watch model based on the 4N21 movement.
Parts List
| K01A79JN02 | crystal - crystal |
| 6M30A3NNG1 | crown - crown |
| 0H1600B01 | case back gasket - case back gasket |
| D0S2BQ | band - band |
| D0S2CQ | band - band |
| 3BA075F1BNG | others - second hand |
| 2BC055A1BNG | others - minute hand |
| 2BC055A1BAA | others - minute hand |
| 1BC035A1BAA | others - hour hand |
| 1BC035A1BNG | others - hour hand |
| 0351155 | others - winding stem |
| DZ0040B01 | others - crown and stem gasket |
| 81606439 | others - bracelet fixing pin |
| 81190055 | others - bracelet fixing pipe |
| 4N21532075A | others - case |
| 82835670 | others - case ring |
| 4N215320 | others - case back |
| 4N2153207HA | others - case |
| 4N212180XS14 | others - dial |
| 4N212190XS19 | others - dial |
| 4N2164 | others - machine code |