In our high-tech world, haulage companies depend very much on suitable transport systems. Many items of daily need have do be collected from the manufacturer and carried from one location to another. Some goods require special transport containers or underbodies. In the heavy goods sector, including excavators, wheel loaders and bulldozers, vehicles were designed with a low platform height to simplify the loading and unloading of heavy construction machinery. The six-wheel semi-trailer is such a vehicle. Produced by several companies, the 14 m semi-trailer's loading edge is 0.80 to 0.90 m from the ground. Axles with twin tyres and a load capacity of 8-10 tons give the hitched trailer a payload capacity of 30-40 tons. Adjustable ramps allow the loading of vehicles without self-propulsion, using grab winches with separate hoisting and discharging drums.