Ammeter/Voltmeter, WWII Japanese Aircraft

This is a Japanese Voltmeter or Ammeter. The scale is labeled to a value of 2.0, and "2000V" is embossed in small lettering in the upper right of the dial, so we aren't sure of the exact function or application. 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 has the "YEW" symbol of the Yokogawa Electric company on the back of the case.

It is in good condition given its age. Measures 1.5 inches diameter and ~1.5 inches deep.The glass and case are intact and the lettering is distinct.