RoadRailers are a unique adaptation of the over the road trailer are were first developed in the 1950's. These lightweight, dual-mode trailers are equally at home being backed up to the loading dock on its rubber tires, or be pulled down the rails in long trains. They have been used by many railroads and companies over the years including, Amtrak, Conrail, Norfolk Southern among others.These Bowser RoadRailer CoupleMate adapters come fully assembled with metal wheels, knuckle coupler with Safety Railings and Steps.