Issued Patents 1989
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4828803 | Swimming pool chemical dispenser and method of making same | Donald Nicholson | 1989-05-09 |
| 4828804 | Swimming pool chemical dispenser with restraining tether | Donald Nicholson, Greg Robert Boyle | 1989-05-09 |
| 4825528 | Chemical depletion signal for a swimming pool chemical dispenser | Donald Nicholson | 1989-05-02 |
| 4822571 | Metering mechanism for a swimming pool chemical dispenser | Donald Nicholson | 1989-04-18 |