 Originally the operating voltage was 750 V DC but this was increased to 900 V DC to give better hauling capacity on the line.Railcars were the chosen motive power from the early days in the main due to the reversal of the trains at Chatel-St. Denis, and this has continued with rebuilt or new modern units, working as single cars or in multiple.Since 1958, goods traffic, much of which is shipped onwards by the standard gauge, has been carried by the narrow gauge by a "piggy back" system where the standard gauge wagons (freight cars) are transported on meter-gauge bogie-trucks.