Loga 30sTt 360 circular duplex slide rule in case 1970 Switzerland

This high quality metal double sided circular slide rule was produced by Loga from Switzerland. This model sTt is from the 1970’s and it looks like the all white version of the 30Tt, just without the yellow accents. It comes in the original cardboard box (some colored pen strips on one side) that has kept it in good condition. There are small signs of use and age but there is a small pit in the black rim and a small knick on the cursor black end. It is fully functioning and has the straight cursor set-up. The diameter of the slide rule is 12,5 cm or 5 inches. Check the attached video on how to work your vintage man tool : slide rule operation instructions!