New Old Stock slide rule by the German company Nestler. This is the model Schul-Rietz (special school edition) with number 0239 from the 1970’s. It comes as a complete set in the original blue vinyl sleeve with outer box, white information sheet (ink can be a bit runny) and short manual in Dutch. It measures ca. 29,5 cm or 12 inches long. The slide rule and the slider are made of plastic and everything is complete. Everything is in great (unused) condition with only small signs of age and storage. Check the attached video on how to work your vintage man tool : slide rule operation instructions!