Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4865489 | Mine roof anchor having adjustable resin retaining washer | John C. Stankus, Glen S. Grissinger | 1989-09-12 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4865489 | Mine roof anchor having adjustable resin retaining washer | John C. Stankus, Glen S. Grissinger | 1989-09-12 |