Nestler 27 Pracision smaller slide rule in case 1940 Germany

Smaller 15cm slide rule that was made by the German company Nestler. This is the model 27 in a very early execution. It comes in the original cardboard signed holder (small hole in top part). It measures ca. 17,5 cm or 7 inches long. The slide rule and the slider are made of wood or bamboo. The slider is reinforced with aluminum around all edges. Nice smaller piece with some signs of age (light discoloration on middle piece) but not used a lot. Check the attached video on how to work your vintage man tool : slide rule operation instructions!