933-3152 Railroad Carfloat KitProduct Information Prototypes for the Walthers Cornerstone Car Float were used in many places where bridges were too expensive or impossible to build. These big barges feature a flat deck with up to three sets of tracks, allowing for quick movement of virtually any rail car over water. These "floating rail yards" were especially common in big city harbors and on many inland rivers, in many cases providing the only rail connection to the main line.