Granted Patent
Utility
US 4,933,093 · App. 07/341,024
Fuel filter
Inventor:
Russel D. Keller
Patented Case
View Patent ↗
Granted: Jun 12, 1990
Filed: Apr 20, 1989
Inventor
Russel D. Keller
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.