Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4848654 | Zone control and smoke damping apparatus for central heating and/or cooling systems | Ruth Zelczer | 1989-07-18 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4848654 | Zone control and smoke damping apparatus for central heating and/or cooling systems | Ruth Zelczer | 1989-07-18 |