Diwa 551-1 Darmstadt slide rule with container 1960 Denmark

This standard size slide rule comes with it’s black and white plastic container both signed by Diwa, the slide rule manufacturer from Denmark. This model is the Darmstadt 551-1 made with scales L,K,A,B,CI,C,D,P,S and T and on the back of the slider LL1-3. Curser is complete with a small crack to the bottom yet fully functional, 2 window in the back are complete and everything is in good complete condition. There are signs of normal use on the items., container is complete and in very good condition as well. The rule  measures 29,5 cm or 11 3/4 inches. Check the attached video on how to work your vintage man tool : slide rule operation instructions!