Operating Era: 1922-1967. This Kit is a Flat Kit. Modeler to specify which RR in comments section on order. Choose from Undec, MC, or NYC. New York Central, Michigan Central. A variation of the USRA steel box car design, NYC purchased 4,000 auto cars for its Michigan Central subsidiary from AC&F and Standard Steel in 1922-23. Many of the cars had their smaller doors permanently closed in the early 1930`s as the Great Depression diminished the market for autos. They were renumbered into NYC series but looked the same as before. The smaller door was stenciled "single door car". By January 1944, 389 cars were so converted. We do not no if the cars retained the small door into the 1950's, but no evidence to the contrary exists. THIS FLAT KIT NOW COMES WITH OUR ONE-PIECE ROOF FRAME.