50' Plug-Door Boxcar Silver Series(R) Canadian PacificDetails: 50' Plug Door Box Car CANADIAN PACIFIC HO Scale. The Plug Door Box Car has a door system that closes with a final inward movement that seals the door flush with the interior of the box car. The design seals the door much better that a traditional sliding door box car. Plug Door Box Cars were used by a wide variety of railroads and other commercial companies. Bachmanns Plug Door Box Cars come in a variety of colors and road names. Each car is