Air Navigation Computer MB-4A, Dead Reckoning, with Dietzgen Divider

Here is an Air Navigation Computer as used by US Air Force navigators from 1940-~1980 for dead reckoning navigation.  This one appears to be from the 1950's.  

Included with the computer is a 14 inch Plotter Type PLU-1/C, and a Dietzgen Divider in an aluminum tube, for measuring and repeating distances on a map.

Computer measures ~5.5 inches wide and ~12 inches long in its case.