Oxygen Master Regulator Mark X, British RAF, 106D/24, For Parts or Repair SN7836 WW1 azimuth and glide slope are

azimuth and glide slope are both checked

both pointers are at the 0 degree position) that can be set at a target degree range by turning the knob

but the book itself and all pages are intact and in very good condition

Here is an Omni-Bearing Selector 336A-2 as used in the 1950's era Collins Radio Navigation System VOR-102

NOTE:  the second pointer is missing

Oxygen Master Regulator Mark X, British RAF, 106D/24, For Parts or Repair SN7836 WW1 azimuth and glide slope areThis 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