This is a quality build pocket slide rule with elaborate calculation options. This great rule also come in the original box with the original leather case as well as additional paperwork and manual. This model is the 4181-1 and in very good condition, from the early 1960’s. The card board box is complete with only a small tear to the sides and signed correctly. The paperwork and manual are in great condition as is the dark green sleeve. This log-log duplex deci-trig measures ca 19 cm or 7 3/4 inches long. Check the attached video on how to work your vintage man tool : slide rule operation instructions!
