Issued Patents 2003
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6581598 | Positive expiratory pressure device | Jennifer M. Foran, Fredrick M. Richards, Christopher Zirps, Robert Elden | 2003-06-24 |
| 6539938 | Maximum expiratory pressure device | Fredrick M. Richards, Deborah A. Laun | 2003-04-01 |