Nestler Elemath projection slide rule box Elemath 1970 Germany

This special slide rule comes in the original and complete cardboard box. Made by Nestler from Germany. This model is for the elaborate Elemath log log model, a special slide rule made for use in the classroom as a teaching aid to be placed on an overhead projector or other beam / light source. It is a very high quality build with a slider and a moving cursor, all made out of separate pieces of Perspex with the possibility to change from right hand to left hand operation. All parts are complete, it is working great and there are only minimal signs of use and age. It is the only overhead model I could find by Nestler. The grey box is complete and in good condition as well. It measures ca 38 cm x 28 cm or ca. 15  x 11 inches. Do check the attached video on how to work your vintage man tool : slide rule operation instructions!