Signal Corps Relay Test Set No I-181B
Missing one knob otherwise appears to be complete. Serial number 29! Manufactured by Marine View Electronics.
From the QSL.net web site:
A portable current flow test set for use in testing and adjusting relays (and similar apparatus) in accordance with electrical requirements for performance of the relay. Provides for application of specified values of current thru the relay winding. May also be used as milliammeter in scale range 0-15, 0-75, 0-150ma.
Click on the thumbnail images to enlarge. Please use your browser's back button to return.