Granted Patent
Utility
US 4,587,677 · App. 06/662,991
Helmet face mask
Inventor:
Leonard W. Clement
Patented Case
View Patent ↗
Granted: May 13, 1986
Filed: Oct 16, 1984
Inventor
Leonard W. Clement
Assignee (at issue)
Cooper Canada Limited
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.