Aircraft Revolutions Per Minute (RPM) gauge, likely to be out of a RAF Gloster Meteor jet.
Ref 6A / 1559. MkllVa. 
20,000 revs. 
 
The Gloster Meteor first flew in 1943 and commenced operations on 27 July 1944 with No. 616 Squadron RAF. The Meteor was not a sophisticated aircraft in its aerodynamics, but proved to be a successful combat fighter.
It was the first British jet fighter and the Allies' only jet aircraft to achieve combat operations during the Second World War (albeit very limited).
Meteors of the Royal Australian Air Force (RAAF) fought in the Korean War. Several other operators such as Argentina, Egypt and Israel flew Meteors in later regional conflicts. Specialised variants of the Meteor were developed for use in photographic aerial reconnaissance and as night fighters.
The Meteor was also used for research and development purposes and to break several aviation records. On 7 November 1945, the first official airspeed record by a jet aircraft was set by a Meteor F.3 at 606 miles per hour (975 km/h). In 1946, this record was broken when a Meteor F.4 reached a speed of 616 miles per hour (991 km/h). Other performance-related records were broken in categories including flight time endurance, rate of climb, and speed. On 20 September 1945, a heavily modified Meteor I, powered by two Rolls-Royce Trent turbine engines driving propellers, became the first turboprop aircraft to fly.
In the 1950s, the Meteor became increasingly obsolete as more nations introduced jet fighters, many of these newcomers having adopted a swept wing instead of the Meteor's conventional straight wing; in RAF service, the Meteor was replaced by newer types such as the Hawker Hunter and Gloster Javelin.
Two Meteors, G-JSMA and G-JWMA, remain in active service with the Martin-Baker company as ejection seat testbeds. One further aircraft in the UK remains airworthy, as does another in Australia.