U.S.A.F. Warbird Flight Simulator Vertical Speed Indictr 580-422

3 1/8" U.S.A.F. Warbird Flight Simulator Vertical Speed Indicator. Manufactured by The Hickok Electrical Instrument Co. P/N 580-422.
Very clean item. It would make an excellent show item of the office or home or as a mock up panel instrument. Operational when removed. I believe it works on 50VDC but not certain. Very hard to come by!!