Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4711160 | Two-piece foundation ventilator | Alvin E. Witten | 1987-12-08 |
| 4587892 | Foundation ventilator | Alvin E. Witten | 1986-05-13 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4711160 | Two-piece foundation ventilator | Alvin E. Witten | 1987-12-08 |
| 4587892 | Foundation ventilator | Alvin E. Witten | 1986-05-13 |