In the United States, large tractor units for long distance heavy duty haulage are typically equipped with a powerful, reliable engine coupled to a sturdy chassis able to support the hauling of heavy half-trailers. Furthermore, the driver's cabs maximise comfort and peak living conditions to minimise the driver's work load. This is achieved by generous in-cab equipment making these vehicles true apartments on wheels. Additionally, a wide range of accessories are provided: extended exhaust pipes, antianimal bars, tanks and alternative finishes strictly chromium-plated in all cases.