Faber Castell Darmstadt 111/54A addiator slide rule pen case 1960 Germany

Early 1960’s slide rule in the original leather green case, by the German company Castell. This is model Darmstadt 111/54A in good condition, the A stands for the Addiator that is incorporated in the back. This gave the owner the means for simple subtractions and addition with the Addiator as well as more complicated calculations with the slide rule..a true hand held calculator. It comes with an original Faber Castell pen that has been made into a stylus. It also has a German manual covering this slide rules functions. I noticed on the back one of the small screws has been replaced. Everything is in good working condition with clear signs of normal use and age, some wear to the original numbered case edges. Priced to match condition. It measures ca. 30 cm or 11 1/2 inches long. Nice all original piece of this well known slide rule. Check the attached video on how to work your vintage man tool : slide rule operation instructions!