By 1907, with more than 3000 Consolidations on its roster, the Pennsylvania Railroad had made the 2-8-0 its locomotive of choice for freight service, and continued refinements produced the H10 class, more than 1,200 of which were built from 1907 to 1915 by the Lima Locomotive Works, the Pennsylvania's Juniata Shops, and the American Locomotive Company in Schenectady, New York. Built for the Pennsylvania Lines West, which operated all tracks west of Pittsburgh, the H10s retained Pennsylvania Lines lettering and assignments until operations were consolidated in 1920, then formed the backbone of the railroad's freight roster through World War I before newer L1s and M1s shifted them into local freight, work train, and yard service; most survived into the 1940's and 1950's as diesel conversion began. Pennsylvania Railroad No. 7688, built by Lima in September 1915, was one of 25 H10s built there for the Pennsylvania that year. Originally assigned to the Cleveland and Pittsburgh, a Pennsylvania Lines West subsidiary, it hauled heavy coal and ore trains between Lake Erie and Pittsburgh's blast furnaces, and after the 1920 consolidation it worked at various eastern points on freight, coal, ore, and maintenance of way trains. Retired in October 1957 at the very end of steam, it was selected for preservation in the Pennsylvania's Historic Collection, and in 1969 it was moved to Strasburg with two other Consolidations that represented the type's earliest design and one of its largest rosters in the world.