Due to the planned conversion of the power supply system of the backbone railway network in the Czech Republic from DC to AC traction, the aim of this project is to modify the railway units Stadler Flirt (EMU480) for operation on lines with AC traction system 25 kV / 50 Hz. The implementation of the project is necessary for the continued operation of Leo Express s.r.o. in the rail passenger transport market in the Czech Republic and the possibility to continue operating transport on the Prague-Ostrava route running after III. TŽK.