The Seiko 2C21-5040 is a watch model based on the 2C21 movement.
Parts List
| ESLN27HN00 | crystal |
| 30N77NA1 | crown |
| 30N77NS1 | crown |
| 0H1650B01 | case back gasket - case back gasket |
| DZ0065B01 | case back gasket - button gasket |
Caliber 2C21
Seiko 2C21-5040 Watch Guide