This headset includes a single earphone and a boom mounted microphone. The headset is mounted on a yoke adapted to fit over a wearer's head with the transducers on either side of the wearer's head. The earphone transducer is in a housing spaced from the wearer's ear and coupled thereto through a flexible...http://www.google.de/patents/US3971900?utm_source=gb-gplus-sharePatent US3971900 - Communications headset with rotatable and tiltable electrical connector
