Oxygen Master Regulator Mark X, British RAF, 106D/24
This WWII-era Oxygen Master Regulator Mark X was used in large bomber aircraft of the British Royal Air Force and Royal Canadian Air Force, such as the Avro Lancaster. The Mk X regulator was for a high pressure continuous flow oxygen system and allowed the pilot to control the flow of oxygen centrally for up to 8 crewmen.
The left hand knob controlled the flow of oxygen, which would be displayed on the ALT gauge. The flow was to be set to match the altitude of the aircraft, up to 40,000 ft. The right hand knob turned the system on and off. The right hand gauge measured system pressure and indicated the quantity of oxygen remaining in the system.
In this specimen, the knobs turn as they should. The top left corner is minimally bent, but otherwise the unit is in exceptional condition. The glass and cases of the gauges (made by US Gauge) are intact and all lettering is clear and precise. Measures ~6 inches wide, ~4 inches tall, and ~ 7 inches long. Its a heavy beast, at 8 lbs.