Nestler 0330 Chemiker slide rule in case 1962 Germany

This interesting slide rule was made by the German company Nestler. This is the model 0330 (successor to the Nestler 33) made for calculating chemical reactions. It comes in an original blue plastic box and with the (handwritten) outer box. The slide rule is made of plastic and the cursor is as well. All parts are complete and it is in working order. The middle part can be reversed for more calculations. It has clear signs of age and use all over, the slider is a bit loose. Everything is readable but the red ink is thinner in several places, there are no chips but there is some yellowing and staining to the plastic body. Inside the box is a formula sheet, but there is also room for a manual (no longer with it) so the slide rule is a bit loose in the box (chemical malformation on the bottom). It measures ca. 29 cm or 11 1/2 inches long. Check the attached video on how to work your vintage man tool : slide rule operation instructions!