The Seiko 8420-6620 is a watch model based on the 8420 movement.
Parts List
| SA9N90SN00 | crystal |
| 25M16EX3 | crown |
| 0Z1700N01 | case back gasket |
| WI083 | others - other band |
| 05R46DSH | others - hour hand |
| 05R46DSM | others - minute hand |
| DZ0041B01 | others - crown and stem gasket |
Caliber 8420
