This straight radiation slider rule is from the cold war era and comes in it’s original case. The slide rule itself was made by Aristo for the Company “Frieseke & Hoepfner”, also from Germany somewhere in the 1960’s. It has an unique and unusual cursor and rubber feet on 1 side. The cursor, feet and slide rule are in great condition, hardly any signs of use or age and fully functioning.  The case has no other name then “Aristo” and has heavy staining on 1 side, but is complete and functional. this slide rule measure  ca. 33,5 cm or 13 1/2 inches. Do check the video on how to work your vintage man tool : slide rule operation instructions!