Norma Gambrinus 190 circular slide rules beer brewing full set 1970 Germany

This is not only a dedicated slide rule for beer brewing and malting. This is also a very high quality metal Norma slide rules, in close to new condition with the original instruction booklet (German language) and case. This also is the large 190 version, with 50cm scale length. It has one of the most manly purposes and is also a feast to behold as well as to use. Special instructions are all in the original 25 page manual. It has a diameter of 19 cm or 7 3/4 inches and is in great condition with. minimal signs of use (some writing in the booklet by the original owner and user). The Norma Company was started in 1959 but these slide rules are probably from the 1970’s considering their pristine condition. I ams also selling some more generic Norma circular slide rules here. Check the attached video on how to work your vintage man tool: circular slide rule operation instructions!