Diwa Pocket-Rietz 601-1 Slide Rule with dark brown leather case. Made in Denmark in early 1960's. Slide rule material: Plastic. Size is 5.5" long. Front Scale K, A [ B, CI, C ] D, L. Back Scale: [ S, S&T, T ]. Cursor: 3 hairlines Promotional slide rule for Renold precision chains of England. Leather case says Renold England, and the back side of the slide rule is printed with Renold England the first name in precision chain. Slide rule is in excellent condition. Case is in very good condition with minor wear and a small scrape on the leather case back.