Voltmeter, 1500V, WWII Japanese Aircraft Constellation The problem with using this

The problem with using this indicator was not only identifying the aircraft

local magnetic variation can be set in at the master indicator so that all indications will be in relation to true north

preservation packaging measuring 4

as used in the US Army Air Force's Boeing B-29 Superfortress (see illustrations of B-29 Flight Engineer's instrument panel showing instrument location)

Voltmeter, 1500V, WWII Japanese Aircraft Constellation The problem with using thisThis is a Japanese Voltmeter, 1500V. It is presumed to be a WWII era indicator used in aircraft of the Japanese Army or Navy. This has not been verified. Aircraft that may have used this have not yet been identified. It is in good condition given its age. Measures 2. 5 inches diameter and ~1. 5 inches deep. The glass and case are intact and the lettering is distinct.