Intermodal container service is one of the most popular types of freight service on rails today. The Maxi-IV car is the mainstay of the U.S. domestic double-stack car fleet. Providing an optimum balance between tare weight and capacity, the Gunderson MAXI-IV is a 3-unit articulated double-stack car that can handle containers from 20-foot to 53-foot long in the well and containers 40-foot to 57-foot in the top, or double-stacked, position. As of a result of its versatility and sturdy construction, the MAXI-IV is now the mainstay of the U.S. domestic double-stack fleet.