|No - 4 in a case
Four road numbers are available per road name
In 1923, the ARA (American Railway Association) proposed a standard design all-steel box car for the railroads. While the design was certainly a good one, the car never became a recommended practice due to questions of the selected inside width. Nonetheless, quite a few railroads opted for the design and rostered sizeable fleets. The largest group of cars, by far, was class X-29 of the Pennsylvania Railroad.