Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4391268 | Solar water heater control and protection system | Donovan B. Mathes, Douglas C. Spreng | 1983-07-05 |
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4391268 | Solar water heater control and protection system | Donovan B. Mathes, Douglas C. Spreng | 1983-07-05 |