The cars were originally single cars with functioning half-width cabs at both ends, but were eventually linked into sets with full-width cabs at each end; however, all cars retain intermediate half-width cabs in the remaining cab positions. All cars running on the ' (based at 240th Street Yard in the Bronx) and almost all cars on the ' (based at the Westchester Yard in the Bronx) are linked as five-car sets, while all cars running on the 42nd Street Shuttle (based at Livonia Yard in Brooklyn) are single cars linked as three and four-car sets; these cars will eventually be linked as six-car sets as a part of an ongoing renovation of the line.