With the electrification of lines around New York City and Philadelphia, the PRR started to build a new series of all-steel locomotive hauled coaches in 1908 which had space for subsequent installation of electric traction equipment. For the Long Island Railroad, production of these coaches started in 1908 and in the beginning, they were hauled by locomotives as intended. When electrification of the line was completed, they received electric equipment for use under 650 V DC. Likewise, more coaches were built for Philadelphia, but equipped for service under 11,000 V AC. Additionally, the West Jersey and Seashore Railroad ordered 16 additional DC vehicles.

The basic passenger variant had 65 seats, but there were also other variants not intended only for passengers. So there were variants with baggage compartments of different size, with either 52 or 40 seats. Another variant was combined of a passenger, a baggage and a mail compartment, with space for only 24 seats. Additionally, there was a baggage-only variant. By 1937, a total of more than 1,400 vehicles had been built. Depending on the variant, they had two or four traction motors with a total output between 400 and 740 hp. These vehicles, commonly called “Red Rattlers”, were used on the LIRR until 1972 and in Philadelphia until 1981.