A "5th Wheeler" is a type of towed caravan, but instead of attaching to the towing vehicle on the normal tow ball, the coupling is located above the rear axle of the tow vehicle (which is normally a ute).

The fifth wheeler concept originated in North America where huge "pickup trucks" are very common. These large vehicles developed a market for very large 5th wheeler caravans (30' and over), and the term "5th wheeler" came to be associated with extremely big rigs. Venture adapted this concept (way back in 1999) by creating a smaller fifth wheeler suitable for towing by an ordinary Aussie ute.