Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4850737 | Hydraulic spring vehicle barricade and hydraulic circuit therefor | James H. Smith | 1989-07-25 |
| 4826349 | Underground vehicle barricade | — | 1989-05-02 |
| 4818136 | Hydraulic vehicle barricade and method | Michael Lippy | 1989-04-04 |