During their career, which began with delivery of the first group in 1917 (except for a 1914 test engine), many members of the PRR's K-4 class were the object of experimentation, upgrading, and other modifications. No. 1120, which belonged to that first 1917 group, was one of four that received a streamlining treatment, designed by Raymond Loewy, of the style depicted here. (No. 3768 had been streamlined in a different style.) An undesignated lensman snapped this view of No. 1120 at East St. Louis, Illinois, on October 6, 1948; Carl Weber provided the image for our collection. The dimensions of the K-4s class are given in the commentary for No. 5492.