When the War Production Board prevented the Baltimore & Ohio from buying diesels during World War II, the railroad ordered twenty 2-8-8-4s of class EM-1 from Baldwin Locomotive Works. Nos. 7600-7619 were delivered in 1944, followed by ten more in 1945. They had four 24x32-inch cylinders and a driver diameter of 64 inches, and sustained 235 p.s.i. of boiler pressure; for other specifications see the following page for No. 7604. After being supplanted by diesels on B&O lines in the Alleghenies these articulateds were placed in service hauling ore trains from Lake Erie ports in Ohio. In 1956 they were renumbered to 650-679 to make room for new diesels, and by 1960 all had been sent to the scrap yard. No. 7601, later No. 651, appears in this Baldwin builder's photo for the 1944 group.