WW1: Aviator's oxygen mask in position and ready to use. Note the handwritten caption on the photo. WW1 planes could not safely fly at 10,000 ft, ceiling for deploying oxygen masks, so the development of the device looked at the future.
Details about WWII Era Oxygen Mask Tank Regulator Eagle Industries Alfco Willson
WWII USAAF Oxygen Mask Tank Regulator Eagle Industries Alfco | Collectibles, Militaria, WW II (1939-45) | eBay!
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