This emergency oxygen mask and hose were carried aboard Apollo 11 in July 1969 and were assigned to Michael Collins.
The mask was a safety precaution in the event of smoke or toxic gasses filling the spacecraft and would have been worn while the astronauts were suiting up. Once the astronauts were suited up and pressurized, the mask could be removed as they could breathe normally.
Transferred from NASA in 1970.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.