WWII Portable Aircrew Oxygen Diluter Demand Regulator. Manufactured by Scott. Type A-15. P/N AD-1876B. Very clean item. Used extensively during WWII on most wartime aircraft. It has a clip on it that attaches to aircrew uniform when used.
It shows very well and it would make an excellent show item of the office or home. Due to its age it is sold for display only. Sold as is, no returns.