The Seiko 5S21-5A30 is a watch model based on the 5S21 movement.
Parts List
| ESDW26SK01 | crystal - crystal |
| 40ME6ES1 | crown - crown |
| 0A2400N01 | case back gasket - case back gasket |
| GK41C | band - band |
| 10TD6RSH | others - hour hand |
| 10TD6RSM | others - minute hand |
| 12ST06DC | others - second hand |
| 0351683 | others - winding stem |
| 5S215A3061 | others - case |
| 82830320 | others - case ring |
| 5S215A30 | others - case back |
| 5S215A50XB19 | others - dial |
| 5S219 | others - machine code |
| 81370146 | others - open-close spring |
| 81503389 | others - screw |
| A200BS | others - push pin |
Caliber 5S21
