Granted Patent
Utility
US 4,791,888 · App. 07/095,434
Water heater tank construction
Inventor:
Otto Z. Vago
Patented Case
View Patent ↗
Granted: Dec 20, 1988
Filed: Sep 11, 1987
Inventor
Otto Z. Vago
Assignee (at issue)
State Industries, Inc.
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.