In 1933, Renault introduced a new type of diesel railcar with mechanical transmission, called type VH. After the first 15 had been delivered to several major French railways, 85 more were built until 1935. Up to this point, all major Railways except the Midi and AL had got the VH. They all got numbers with the prefix “ZZ”. Power came from a Renault V12 Diesel delivering 220 hp to a four-speed gearbox that was connected to both axles of one bogie. The engine was located in one of the two cabs. A long radiator on the roof led to the nickname “Iroquois”.

In 1938, the railcars from all railways came to the SNCF and were renumbered with the prefix “ZZR”, with the additional letter denoting the manufacturer. Later they got the new prefix “X”. Between 1944 and 1950, nine had to be withdrawn after damage in the war. Soon the others were modernized in several aspects, with new engines delivering 300 hp. After their withdrawal in the seventies, two have been preserved. While one is on display in Mulhouse, the other one is operational.