The Seiko 8420-5089 is a watch model based on the 8420 movement.
Parts List
| ES3N02SN | crystal |
| 25M04NA1 | crown - crown |
| 0G1900N01 | case back gasket - case back gasket |
| 0Z0034B01 | case back gasket - crown and stem gasket |
Caliber 8420
Seiko 8420-5089 Watch Guide