The Front Runner with Union Pacific trailer Bachman trains 48401 is a ready-to-go model train set featuring a locomotive from the Williams by Bachmann brand. This O gauge train set is powered by AC and has a scale of 1:48, replicating the Union Pacific railroad. The locomotive is made of plastic and diecast materials, with a color design of yellow and gray. The control system is analog, allowing for easy operation on a 3-rail-2-conductor rail system. Perfect for model railroad enthusiasts looking to add a piece of Union Pacific history to their collection.