The ET42 is a two-section locomotive for freight traffic on lines with 3 kV DC. After the ET40 that had been built in Czechoslovakia and the ET41 that had been built in Poland, the ET42 came from Novocherkassk. It was based on the VL10 and VL11 and was the only electric locomotive in Poland that had been built in the Soviet Union. Each section has four axles with a total output of 4,840 kW. Both sections together have a total weight of 164 tonnes and a starting tractive effort of 560 kN. Their main task are heavy freight trains between Upper Silesia and the Baltic ports.