Oxygen Master Regulator Mark X, British RAF, 106D/24, For Parts or Repair SN172 TBM Avenger and has a serial number

and has a serial number prefix of AF-51 indicating a year of manufacture of 1951

It may be some sort of a stall warning instrument

It is clearly 'experienced' but the dial markings are clear and the glass and case are intact

the tube provides air pressure measurement for pitot-static instruments

Oxygen Master Regulator Mark X, British RAF, 106D/24, For Parts or Repair SN172 TBM Avenger and has a serial numberThis 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