On January 1, 1918, control of US railroads was taken over by the United States Railway Administration (USRA). The USRA employed top locomotive designers from several builders and railroads to develop a standard line of locomotives of various sizes, sharing certain basic parts to reduce production, maintenance, and operating costs. Eventually, twelve standard designs were settled on. These designs included wheel arrangements from 0-6-0's to 2-8-8-2's. Three sizes of tenders were developed with 8000, 10,000 & 12,000 gallon capacities. Some locomotives were developed in both light and heavy versions such as the popular 2-8-2 Mikados. While the heavy Mikados ran on about 23 railroads, the light ones were used on over 50 different railroads in both freight and passenger service. The first USRA locomotive rolled off the line in July 1918. Built by Baldwin, it was #4500 for the Baltimore & Ohio railroad. The light Mikados has 63 inch drivers, 26" x 30" cylinders, ran 200 lbs. of boiler pressure, and weighed 290,800 lbs. They had a tractive effort of 54,600 lbs. and originally cost $53,600. These engines were built by several builders including Alco, Lima, and Baldwin. 1,865 USRA locomotives were built and were so successful that in later years, many copies were made, ending up in a total of 5,107 engines being built to USRA designs. In February 1920, the USRA was officially dissolved.