Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| RE40764 | Two-piece valve stem seal | Tigree Milam Butcher | 2009-06-23 |
| 6901902 | Two-piece valve stem seal | Tigree Milam Butcher | 2005-06-07 |
| 6428013 | Reverse seal | David E. Johnston, David Sakata | 2002-08-06 |
| 5775284 | Two-piece valve stem seal | Karry S. Kirchner | 1998-07-07 |