VEB Mantissa Masse machine time slide rule full set 1977 GDR Germany

This double sided full plastic slide rule comes in its original grey cardboard box and with German manual. It is the “Masse” or in English the “Sizing” slide rule. It was made by VEB Mantissa from the GDR/DDR (Eastern Germany) in 1977 (according to the manual). There are indications and scales specially for easy calculation of sizes and corresponding weights for profiled rods, plates and beams. It has standard body with simple cursor and it measures ca 33 cm or 13 inches. It is in good condition with minimal signed use but some signs of aging (some yellowing). Do check the attached video on how to work your vintage man tool : slide rule operation instructions!