Issued Patents All Time
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6156089 | Two-stage air filter with multiple-layer stage and post-filter stage | Edward C. Sofsky | 2000-12-05 |
| 5922096 | Forced air system air filter | — | 1999-07-13 |
| 5858045 | Multiple layer air filter media | Edward C. Sofsky | 1999-01-12 |
| 5704953 | Forced air system air filter | — | 1998-01-06 |
| 5571300 | Frame and pad filter system | — | 1996-11-05 |