The range of this RPM Gauge suggests usage in a de Havilland Gipsy Major engined aircraft.
The obvious contender is the DH82 Tiger Moth; but any de Havilland-engined types would have the same instrument.
It doesn't end there, though.
Many other types used the Gipsy Major, including Miles Aircraft; Percival Aircraft; early Austers, some Airspeed types, and even the Belgian Stampe SV4 Biplane.
It all depends on what further markings are on the instrument. If it has the "A crown M" then it is Air Ministry and RAF. The date should help. It is usually a two figure number after the instrument serial engraved on the dial face behind the pointer in the vicinity of its pivot pin.