The Seiko 2C21-0100 is a watch model based on the 2C21 movement.
Parts List
| 180A02JN02 | crystal - crystal |
| 35NR5NA1 | crown |
| 35NR5NS1 | crown |
| 0H1450B01 | case back gasket - case back gasket |
| DA22A | band - band |
| DA23A | band - band |
| 07P29NGM | others - minute hand |
| 07P29NSM | others - minute hand |
| 07SC17NS | others - second hand |
| 1AA047A1BNG | others - hour hand |
| 1AA047A1BNS | others - hour hand |
| 2AA070A1BNG | others - minute hand |
| 2AA070A1BNS | others - minute hand |
| 3BA075F1BNG | others - second hand |
| 3BA075F1BNS | others - second hand |
| 07SC17NG | others - second hand |
| 0351225 | others - winding stem |
| 82707430 | others - case ring |
| 2C21010025 | others - case |
| 2C2101002E | others - case |
| 2C210460XS13 | others - dial |
| 2C210460XS14 | others - dial |
| 2C2110 | others - machine code |
| A110AS | others - push pin |
Caliber 2C21
