Issued Patents 2004
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6835343 | Method for handling concrete retaining wall blocks | Benjamin R. Manthei | 2004-12-28 |
| 6715965 | Retaining wall blocks and retaining walls constructed from such blocks | Benjamin R. Manthei | 2004-04-06 |