This is the HO Scale Through Plate-Girder Bridge - Kit - Build as Single or Double Track from Walthers.
Whether a small stream or a busy highway, railroads have long relied on bridges to carry the right-of-way safely across natural and man-made obstacles. One of the most common railroad bridge designs is the through plate girder. Used for many decades, this design is constructed of several steel sections riveted together to form girders. They're known as through types as the track passes between, rather than on top of the spans. Bridges of this type are typically used to cross short distances of about 30 to 100' 9.1 to 30.4m.
This model is typical of railroad bridges found all over North America from the steam era to the present day. The kit can be built either as a single- or a double-track bridge. Each includes parts for two complete spans, but the design makes it easy to combine additional kits (sold separately) to build a longer or wider bridge if needed. The plastic parts are molded in color and feature authentic rivets and other fine details. Easily installed in new or existing layouts, the kit includes complete instructions.