Sennheiser HMEC 460 Instructions For Use Manual page 8

Adaption to the aircraft intercom system via mono/stereo switch
Separate volume control for left and right channel
Boom switch for microphone boom left/right position
With the NoiseGard active noise compensation switched off, the headset can be used
as a conventional headset
"Audio-In" signals from the 3.5 mm jack socket mute automatically in the presence
of intercom and/or RT traffic
2.5 mm jack socket for connecting a mobile telephone
3.5 mm jack socket for connecting a portable audio player
Three options for powering NoiseGard
(on-board power supply system, cigarette lighter socket or batteries)
Fail safe operation in case of power failure
10-year warranty and "Made in Germany"
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