Standard Slide Rule in the original box by Aristo made around 1970. Model nr. 0903 (see 0903LL version here). Made in Germany. It is 32,5 cm / 13 inch. It is an Arsito-Scholar with 10 scales on the front and cm / inches on the back, so 12 in total. The slide rule, the slider and the case are made of plastic. Piece is in used condition.