IP Library › Granted Patent US 4,538,820
Granted Patent Utility
US 4,538,820 · App. 06/507,274

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Inventor: Henry S. Duffee
Patented Case View Patent ↗
Granted: Sep 3, 1985 Filed: Jun 23, 1983
Inventor
Henry S. Duffee

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Quick Facts
Patent No.
US 4,538,820
App. No.
06/507,274
Filed
1983-06-23
Granted
1985-09-03
Kind
A