The 1949 Tube Stock was composed of ninety-one cars built by the Birmingham Railway Carriage and Wagon Company in Smethwick, England. These cars were identical to the earlier 1938 stock with which they were used. They were built for use on a planned extension of the Bakerloo line to Camberwell, but, after the extension was cancelled, they were also used on the Piccadilly, and Northern lines. The first cars were taken out of service in 1972. The last UNDM, 31030, was withdrawn in 1973, while the last trailer, 012498, was withdrawn in 1978.