Aristo 0971 Hyperbolog slide rule case feet 1970 Germany

This is a great duplex slide rule made by Aristo from Germany. The sturdy container has kept the slide rule in good condition and it also comes with the original Aristo nr. 1364 tab inlay sheet as well as the original 2 separate feet. This model is 0971 HyperboLog double sided with rubber feet on both sides. A special rule for Hyperbolic functions. Everything is complete and in good condition with only small some signs of use and age including a little fling to the yellow. The rule measures 33,5  cm or 13 1/4 inches. Check the attached video on how to work your vintage man tool : slide rule operation instructions!