5/12/20 - This is an authentic, exceptionally well-made, near perfectly preserved WW2 German Army Artillery Calculator. The calculator itself is "Eagle 538" waffenamt and has a "cme" makers mark. The top flap of the black leather case is marked "K.W. 140". The inside of the case is marked "Ertel" and has an "Eagle 112" waffenamt. The case is minty except for very light surface scuffs throughout and very minor cracking on the top flap where it creases. This was also featured in a recent Youtube video. Link below!
https://www.youtube.com/watch?v=7oGoWyMqbO0&t=1s