Altimeter, Sensitive, RAF MK XIVA 35K FT SBD Dauntless with two clamping screws

with two clamping screws

and this is the indicator which appeared on the pilots instrument panel to provide directional indication for the signal being received from the transmitting installation

the unit indicated fuel quantity in four tanks: left

The knobs are stiff but rotate

Altimeter, Sensitive, RAF MK XIVA 35K FT SBD Dauntless with two clamping screwsHere is a WWII era Sensitive Altimeter Mk XIVA 6A 1703 as used in aircraft of the British Royal Air Force, such as in versions of the heavy bomber Lancaster and fighters Spitfire and Beaufighter. The Sensitive Altimeter displayed altitude up to 35,000 ft using 3 pointers. The first and longest indicated 100's of feet, the second indicated 1000's of feet, along the outer scale, and the third and smallest indicated 10,000's of feet. on the inner scale.