Symbol 0244 from ISO 7000 - Title/Meaning: Signal horn 
Function/description: To identify the control for the horn which emits a sound, usually intended to alert persons in the vicinity to the presence of the equipment or vehicle.
Own work using: iso.org/obp/graphics/grs/d4fba3f3-13c5-4b45-a806-586102853086 200.png
Vectorization:  Mrmw