Vector Plotting Machine AN-5748 in Original Packaging

Here 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, measuring 22 x 10 x 4 inches.