Granted Patent
Utility
US 4,564,190 · App. 06/497,205
Appliance for practicing aquatic sports
Inventor:
Otto Frenzl
Patented Case
View Patent ↗
Granted: Jan 14, 1986
Filed: May 23, 1983
Inventor
Otto Frenzl
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.