Issued Patents 1989
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4886093 | Vent valve of an air pump | Tsuyoshi Itakura | 1989-12-12 |
| 4880549 | Method of filtering in an aquarium tank with a filter envelope | Klaus Woltmann | 1989-11-14 |
| 4861468 | Rotor impeller assembly | Jonas Ivasauskas | 1989-08-29 |
| 4842726 | Inside filter for aquariums | — | 1989-06-27 |
| 4842727 | Aquarium filter | Klaus Woltmann | 1989-06-27 |