The Seiko A639-5020 is a watch model based on the A639 movement.
Parts List
| BA0W97LN00 | crystal |
| FH2980B0B | case back gasket |
| EB0075B0A | case back gasket - button gasket |
Other models with the same movement
| A639-5000 |
| A639-5009 |
| A639-5010 |
| A639-501A |
| A639-5029 |
| A639-502A |
| A639-5030 |
| A639-5039 |
| A639-5050 |
| A639-505A |
| A639-5060 |
| A639-5070 |