Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| D434158 | Ladder step extender | Donald R. Armstrong | 2000-11-21 |
| D409765 | Ladder step extender | Donald R. Armstrong | 1999-05-11 |
| D390669 | Ladder step extender | Donald R. Armstrong | 1998-02-10 |