All HELLE Carriages are prewired, prehosed, and factory tested. The pumping unit on our carriages are self contained and there are no hoses over the pantograph. HELLE was the pioneer in the double 80 roller chain, no rack and pinion. The guide wheels on each carriage are hexagon style wheels that wear up into the wheels to maintain accuracy. Four trucks are standard with 10" wheels, 14" wheels optional. To adjust your thickness on your sets, all you do is flick a toggle switch in the cab, what could be easier?? No more getting out of the cab and wasting time! HELLE pioneered the structural tube frame, making it much stronger than channel iron or I beam frames. The carriage frame can be made to fit your track, or we can make you a sub frame. Our knee plates are wrap around and have replaceable wear plates made of fiber wear strips.