Issued Patents 2019
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10349178 | Microphone diaphragm | John S. Lettow, Kenneth E Fritsch | 2019-07-09 |
| 10176937 | Electrical switches and sensors | John S. Lettow, Terumi N McKenna | 2019-01-08 |
| 10166811 | Security devices | John S. Lettow | 2019-01-01 |