Faber Castell projection slide rule 310/80 box 1960 Germany

This special slide rule comes in the original and complete cardboard box with manuals and accessories. Made by Faber Castell from Germany. This model is the 310/80 for the Mentor 52/80, a special slide rule made for use in the classroom as a teaching aid to be placed on a 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. All parts are complete, it is working great and there are only minimal signs of use and age. The green box is complete and in good condition as well, just some of the gold is missing from the letter on top. It measures ca 38 cm x 17 cm or ca. 15  x 7 inches. Do check the attached video on how to work your vintage man tool : slide rule operation instructions!