You are bidding on a New NOS Sierra Madre CA Flight Crew 51-MA-25 Nasal Oxygen Mask Part No. 358-61. Item is sealed in plastic bag and appears to be new old stock. This belonged to a retired airline pilot. I am not sure of the era and I didn’t want to break the seal given the rarity. Shipping will be 9.95.  I only ship to the continental United States.