Reading Company C1a Class
 The C1a Class were a type of 4-4-4 steam locomotive built for the Philadelphia and Reading Railway in 1915. Four locomotives were built road numbers #110-113. They used front and rear trucks that were effectively identical. During a year of operation they proved to be quite unstable; after that year they were rebuilt to 4-4-2 Atlantic locomotives reclassified as P7sa and renumbered #350-353.