A great example of a WW2 era signal lamp with coloured filters (red/green/yellow/clear) also present. Untested/Unwired plug. Indicates 24 volts for anyone looking to refurbish and bring back to life.

Made by Grimes in Urbana, Ohio. Manufactured for the US Army, Navy and Air Force. In all likelihood also used by other Allied nations during wartime.

These lamps were used by bomber crews, normally tail gunners in B-17s, to communicate using morse code. Similarly in Army and Navy settings.