Royal 1091 Universita slide rule full set Japan 1970

From Japan is this Royal No. 1091 Universita slide rule. These Royal slide rules are a bit of a mystery. They are probably produced by Uchida Yoko Company, but the Universita is Italian while the booklet comes in Dutch. Made in the 1970’s complete with the original green and yellow-white plastic box, dedicated outer box and  manual both showing this exact rule. I believe it was the most powerful from the range of Royal branded slide rule models. It features 23 scales all together and a 7 hair line cursor. It measures ca 34 cm or 13 3/4 inches. Slide rules and cursor completely made of plastic, all complete and in very good condition with only minimal signs of use and age. Outer box is complete with storage marks.