Blue-flagged and awaiting its next call to duty, Union Pacific 9908 sits at the north end of UP's Dolores Yard in Carson, California, on November 10, 2016. Built as UP SD60M 6341 in September 1992, this engine was rebuilt by Progress Rail into (choose one) an SD59M-2 / SD33ECO / SD59MX. (PRI calls these SD33ECO, and EMD refers to them as SD59M-2. Meanwhile, UP classes them as SD59MX.) Photographed on railroad property with permission and full PPE.