B unit
These are all known B unit models, with discrepancies settled by the later (Marre) reference. At least one of each model was manufactured. All units below contain one or more engines and traction motors, so slugs and snails are not listed. Cow-calf units are also not listed, since these were considered a single locomotive. The New York City Revenue cars 66 and 67 were R8A units which were B units also.