Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4811221 | Simplified battery operated automatic and manually operable valve | Benjamin Grill, Walter L. Harrison | 1989-03-07 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4811221 | Simplified battery operated automatic and manually operable valve | Benjamin Grill, Walter L. Harrison | 1989-03-07 |