Granted Patent
Utility
US 4,267,722 · App. 06/063,084
Adjustable lubrication quality indicator-protector for engines and other machines
Inventor:
Harold M. Hendry
Patented Case
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Granted: May 19, 1981
Filed: Aug 2, 1979
Inventor
Harold M. Hendry
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.