Radar Pressure Indicator, 0-25 PSI ABS, AW 1 7/8-31-B2F29 Martin The scale is interesting in

The scale is interesting in that the long pointer rotates clockwise from the 6 o'clock position indicating altitude in 100 Meters per index tick mark along the outer scale

The scale reads from -50degC to 175degC

Here is a WW2-vintage electrical Free Air Temperature Indicator

Flange diameter

One or two gyro units almost identical in appearance with the C

Radar Pressure Indicator, 0-25 PSI ABS, AW 1 7/8-31-B2F29 Martin The scale is interesting inHere is Radar Pressure Indicator use in radar equipped aircraft during late WWII and post WWII. It is in decent condition for its age. Measures ~2. 25 inches diameter and ~2 inches deep. See photos.