This Norma Merkuria 100 was the “Commercial” slide rule for the businessman or trader (Kaufmann). The slide rule is a complete set with booklet in German and an extra chart in the original sleeve . Everything is fully functioning and in good condition with small signs of use and age. The diameter of the slide rule is 10 cm or 4 inches. Check the attached video on how to work your vintage man tool: circular slide rule operation instructions!
