Unknown Optical device by Kern Company

[Trevor]

Hello,

 

I recently inherited some kind of US military optical device that I think could be from the 1940s-1960s. There is a marker on the base that says “Kern Company New York”, so I looked them up and they made civilian survey equipment, and several types of military optics. Unfortunately they went out of business in 1991 so I can’t ask the company what this is, but I did look through several lists of products and have been unable to find anything like what I have. I am fairly certain that this is US military though for several reasons.
 

The base measuring disk appears to be identical to the WW2 US M1 and M2 aiming circle, but the rest of the device is completely different.

 

The top scope is detachable from the base and looks very close to the US M49 spotting scope. In fact I was able to use the lens covers and the 20x eye piece from a M49 on this other device. The only difference between an M49 and my device is that there is a bulge on the right side of my scope that has a threaded opening. It looks like some kind of accessory port, but that is just a guess.

 I will include several pictures below.

 

Does anyone have any idea what this was used for, and what that port on the side of the scope was?

[Trevor]

[Trevor]

[Proud Kraut]

Since this scope is U.S.  made I would post it at our sister forum, the U.S. Militaria Forum as well.

 

https://www.usmilitariaforum.com/forums/

[Trevor]

Would anyone know a shop or museum that I could contact to figure out what this is?