Granted Patent
Utility
US 4,539,715 · App. 06/487,878
Size adjustable helmet
Inventor:
Leonard W. Clement
Patented Case
View Patent ↗
Granted: Sep 10, 1985
Filed: Apr 22, 1983
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.