The Seiko 2C20-5100 is a watch model based on the 2C20 movement.
Parts List
| RE7N79HN00 | crystal |
| 30N77NA1 | crown |
| 30N77NS1 | crown |
| 0H1800B01 | case back gasket - case back gasket |
| DZ0065B01 | case back gasket - button gasket |
Caliber 2C20
Seiko 2C20-5100 Watch Guide