Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5788843 | Method and installation for treating water | David King, Everett John Wegerif, William Powell Nairn, Hershel Williamson, Gary Heller +1 more | 1998-08-04 |
| 4790577 | Door push-bar lock-out retainer | Curtis L. Helding | 1988-12-13 |
| 4331354 | Door push bar lock-out retainer | Curtis L. Helding | 1982-05-25 |