Medium frequency, direct current (MFDC) inverter technology, microprocessor controlled resistance (spot) welding machine. The innovative Smart Autoset technology, thanks to the automatic recognition of the materials and thickness, eliminates set-up times and guarantees optimal spot welding even if the types of steel to be processed are not known. It is particularly suitable for body shop applications and industrial use and gives excellent results also on high strength steel (HSS)/boron and galvanised metal sheets.