Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4760935 | Plastic closure plug | Paul Christiaan H. van den Beld, Gerhard Kettenring, Gunther Schmitz | 1988-08-02 |
| 4588105 | Sealing plug | Gunther Schmitz, Gerhard Kettenring | 1986-05-13 |