This iron sesqui-oxide 40' USRA steel box car with single door, flat roof and side brakewheel runs on black Bettendorf trucks. This USRA class X29 steel box car was one of more than 1,200 box cars from more than one series used in express and bulk mail service on the head of passenger trains. The X29 was a popular choice due to its low profile that allowed it to move under the wire into Penn Station, New York.