The D-Type cars were the first articulated rapid transit rolling stock in US history when they debuted on the BMT in 1925. Each of the 121 cars built consisted of three sections with an articulated joint between each car. These cars also featured front destination signs with a route designation and side signs that could illuminate the direction in which the train was traveling. Although the BMT continued to order articulated trains until its acquisition by the City of New York in 1940, New York City Transit did not order any articulated trains until placing the R211 order in 2018. Three D-Type sets were preserved, two of which are used on fan trips and are displayed at the New York Transit Museum. The third set is in storage as of June 2015.