Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4854543 | Apparatus for forming an opening with a gasket in a masonry manhole | Emile Gonthier | 1989-08-08 |
| 4842785 | Method for installing gasket in a poured concrete structure | Emile Gonthier | 1989-06-27 |