Siemens valves and flaps slide rule 1960 Germany

This Siemens marked and made slide rule comes in the German language and has no makers mark. This special slide rule comes in the original signed sleeve and with a dedicated double cursor with 2 centre hairlines and multiple small red headlines on 1 bottom half. Very interesting extra use of the cursor for temperatures. Information on Gasses, Steam vapor and fluids for Siemens engineers and for internal company use only. It is in good condition with some signs of use and age. It measures 25 cm or 10 inches. Do check the video below on how to work your vintage man tool : slide rule operation instructions!