Airspeed Indicator 320 MPH Mk IXD Ref 6A/415 RAF
This is an excellent example of a WWII-era Air Speed Indicator Mark IXD, Ref 6A/415, as used in the British RAF Fairey Battle bomber and the Airspeed Oxford utility aircraft. This particular specimen has a serial number showing a year of manufacture of 1939.
Air speed from 0-200 MPH is indicated by a clockwise-rotating pointer, starting at the 6 o'clock position, along the outer perimeter scale. As the aircraft passes 200 MPH, air speed is indicated along the inner scale up to 320 MPH.
The indicator measures ~3.5 inches diameter and ~2.5 inches deep. The glass and case are intact and dial markings are clear and precise. The crown symbol of the Air Ministry can be seen stamped on the rear case.