Issued Patents All Time
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4258793 | Oil well testing string bypass valve | John C. Zimmerman | 1981-03-31 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4258793 | Oil well testing string bypass valve | John C. Zimmerman | 1981-03-31 |