Each triplex replaced three ordinary helper engines, and the new locomotives worked well enough to_ stay on the Erie roster for more than a decade. But _the design proved a bit over the top and only one more Triplex was ever built, for the Virginian Railway. Even with their huge boilers, the locomotives could only make enough steam to go 10 mph. One reason was poor draft in the firebox, because only the front cylinders exhausted through the smokebox and created draft; the rear cylinders exhausted through a separate smokestack on the tender. Another inherent problem with the design was that traction from the rear engine decreased as the boiler used coal and water and the tender got lighter.
The RailKing Imperial Triplex recreates the flamboyance of the original design but runs better than the proto- type ever did. Features include a die cast boiler and chassis, die cast tender body, authentic paint scheme, metal handrails and whistle, metal wheels and axles, constant voltage headlight, prototypical Rule 17 lighting, two precision flywheel-equipped motors, synchronized puffing ProtoSmoke(TM) system, speed control in scale MPH increments and Proto-Sound 3.0 with digital command system featuring freight yard Proto-Effects. Operates on O-42 curves.