A little story about them: My great grandfather brought these from the war(I'm guessing like war loot), he was not with Germany, he was a commissar in the JNA(The Yugoslavian Partizan army), so the binoculars should be from around the Balkan region if it helps. I would really love to know when they were made, since I've been looking all over the internet and I didn't find where the serial number matched. It's roughly 400 grams heavy. It has angle marker on the lens. If you could tell me anything about the binoculars I would be very grateful Here are some pics of the binoculars: http://imgur.com/a/pWRNy
Edit: Forgot to say, it is possible they are made from 1914-1940 from what I've heard. Probably around 1928 because of the 400 grams.
I can't comment on that particular model, but Zeiss is a very old and reputable optics company. You may have some luck if you contact Zeiss with these pictures directly. They have their own museums in Germany, I'm sure their staff would be pleased to help you with details concerning finishing materials and such, which may escape inexpert observers.
standard service binoculars, nothing special about them.
The serial number indicates the production year, IMO it should be more 1940 than 1928.
Here is a thread with more info http://forum.axishistory.com/viewtopic.php?t=37513&highlight=dienstglas
Contact Carl Zeiss Jena directly if you want to get more information.