In the UK and EU roads are smaller and turn more. Trucks have to be shorter. Most are cab-over-engine models (COE). The driver sits over the engine and the front of the cab is flat. Shorter trucks can weigh more. Trailers can have three axles under the load, and short semi-tractors with two axles. These have the same weight and number of axles as a long semi-truck. They take up less space and can turn better.