During World War I, the United States Railroad Administration (USRA), began designing a new standard freight locomotive to be used for freight purposes. The USRA designed these locomotives with a 2-8-2 Mikado wheel arrangement and when they were built, were considered to be one of the most modern locomotives at the time. The design was very popular with the railroad companies, as the American Locomotive Company (ALCO), Lima Locomotive Works, and Baldwin Locomotive Works ended up producing over 600 of these machines. They were used on many different railroads including: The Rock Island Railroad The Baltimore & Ohio Railroad The New York Central Railroad The Nickel Plate Road The Frisco The Southern Railroad The Western Pacific The Union Pacific The Grand Trunk Western and many other short-line and subsidiary railroads as well. If these locomotives were to be added, the customization factor could be huge. There can be so many paint scheme and whistle variants of the locomotive (kind of like the S160s) due to their wide-spread use.