For the Pennsylvania Railroad (PRR). This specific 4-car model railroad set. Replicates North American streamlined passenger fleets from the 1940s to the 1960s. Included Cars & Road Numbers. The four distinct cars contained in this box set include. Railway Post Office (RPO). N Scale (1:160). Standard Kato operating magnetic knuckle couplers for easy coupling. Low-flange metal wheels and axles. Features detailed molded car interiors. Interiors can be fully illuminated using separate Kato passenger car lighting kits (#11-204 or #11-206).