Road-Rail cable trailer PTT 4500 DUOTRAM is one-axle trailer equipped with wheel units assembled on swivelling half-axles. Trailer service weight is 1500 kg, payload (loading capacity) is 3000 kg, and total weight incl. load is 4500 kg. Trailer is designed for ride, coupled to trailer vehicle by means of coupling of 40 or 50 mm diameter. Trailer coupling is vertically adjustable. Maximum diameter of cable drum is 2200 mm. Cable drum is positioned on drum axle rotating in slide bearings (for easier cable unwinding).  Cable drum is positioned in sliders of the main lifting units. Road/Rail cable trailer can be equipped with different types of main lifting units control mechanisms as well as with other auxiliary equipment.  Cable trailer is equipped with rail gear unit for ride on rails, also on rails of tramway tracks. Rail gear unit is part of the trailer and is controlled hydraulically, for quick alteration from ride on road to ride on rails. Optionally, trailer can be equipped with brake to brake the unwound cable while installing OLE wire.