The Illinois Central’s use of the “Enterprise” design 33’ offset-side twin hopper was unique among the railroad industry. The differencein design from other offset-side twin hoppers would not have been significant except that the IC fleet was so large at over 12,000 cars. Whilenot as large as other fleets of 33’ AAR design offset twin hoppers such as the C&O (27,490), B&O (21,300) and L&N (19,200), the IC rosterwas a major part of the nation’s freight car mix, with cars being seen throughout the country.From 1937 to 1949, thousands of IC offset twin hoppers were manufactured by a variety of builders, including the railroad itself. The“Enterprise” design became the IC’s standard for hopper car design for twelve years. The first cars from Pressed Steel Car Company’s Hegewisch, IL plant (formerly the Ryan Co.) came in 1937 and were originally numbered in the 209000-209999 series. Another batch of carsin 1937 came from GATC in the 219000-219999 series. Both orders of cars were quickly renumbered into the 68000-69899 and 69000-69999 series. The next blocks of cars came from Pullman: 750 cars in 1940, the 71000 series, and 100 cars in 1941, the 72000 series. Prewarcars lacked the slope sheet brace and were equipped with ladders instead of grabs at the corners.