Nestler 0440 Maarschalk Concrete slide rule Germany 1960

This is the standard version concrete slide rule by Nestler from Germany. It does not have a number on it but it seems to be model 0440. This slide rule is for calculation of reinforced concrete (Stahlbeton) per the system of Maarschalk (n= selectable). It has a special scale on the front including some formulas, on the back are normal calculating scales. It has the original leather sleeve with Nestler name. It has metal reenforced ends with good rubber feet. It is all complete but in used condition, on the normal scales there is some bleeding of the ink (priced accordingly), the unique cursor is in great conditions is the Maarschalk front side. It measures ca. 35 cm or 14 inches long. Do check the video below on how to work your vintage man tool : slide rule operation instructions!