The increased volume of coiled steel transportation gave rise to a new purpose-built freight car. Previously rolls of coiled-steel had generally traveled in specially equipped gondola cars. In the 1960s a lighter type of car emerged specifically for hauling coils of steel in an integral trough. The car type gained popularity and eventually over 17,000 cars were built. Atlas’ model replicates a 42’ design with a distinctive fishbelly side sill.