Really neat folder containing quite a bit of information for the 1950's Train X which was promoted by the Chesapeake and Ohio and eventually became the New York Central Explorer. Includes marketing materials and correspondence, internal correspondence and progress reports, promotional photographs, interior concept photos, consist sketches, and much more. The folder is about a half inch thick. See photos for best description. The photos in this group were at one time part of the Pullman-Standard engineering photography archive.