Scott Airline Passenger Oxygen Mask
The Scott Airline Passenger Oxygen Mask featured a yellow rubber oronasal cup, with a clear rubber bag attached to a thin rubber hose. The hose was connected to the airplane's supplied air system, and the unit would automatically drop down in case of emergency. This example was from a DC-9, and was made by Scott Safety in 1997.
Similar masks in my collection: Scott Sky Mask