Vector Plotting Machine AN-5748 in Original Packaging Bf-109 and the unit is 14

and the unit is 14 inches high

Here is a nice specimen of a WWII-era electrical Switchable Tachometer

It was made for an order by the Air Corps US Army (as evidenced by the embossed AC US ARMY) in 1937 (further evidenced by the serial number prefix AC-37)

This is an original (not a photocopy) Flight Manual for the iconic F-4B Phantom jet fighter of the US Navy NAVWEPS 01-245FDB-1 published Jan 15

Vector Plotting Machine AN-5748 in Original Packaging Bf-109 and the unit is 14Here is an authentic WWII era navigational plotter used by aircraft navigators to plan, plot, and track their course along a chart. The plotter would be affixed to a navigator's map table and laid upon the map of the flight plan, typically in a large aircraft. It is essentially a flight computer as it provides the navigator with the integral calculators for heading, track, true air speed, and ground speed. This example is in its original packaging,