04087653 is referenced by 26 patents and cites 4 patents.

A head gear assembly including first and second sound attenuating earcups and means for supporting the earcups over the ears of a wearer and in which each of said earcups has an earphone therein, one of said earcups has a contact microphone therein and switch means is provided for enabling said contact microphone while disabling the earphone in the cup in which the contact microphone is located.

Title
Sound attenuating earcup assembly provided with receivers and contact microphone
Application Number
641450
Publication Number
4087653
Application Date
November 5, 1976
Publication Date
May 2, 1978
Inventor
Jackson A Aileo
Carbondale
PA, US
Leonard P Frieder Jr
Dalton
PA, US
Agent
Shenier & O Connor
Assignee
Gentex Corporation
PA, US
IPC
H04R 1/10
H04M 1/05
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