Symbol 5081 from IEC 60417 - Title/Meaning: Loudspeaker/microphone Function/description: To identify the talk/listen button.
Additional information: 
See also symbols 5080, 5126 and 5127
Published in: First edition, 1973
Own work using: iso.org/obp/graphics/grs/1c431222-688b-47bf-bd4d-e3e057e96e39 200.png
Vectorization:  Mrmw