Demonstrates the work by the BTPS for a overseas visit to the Museum in 1980.Folded card used as a cover for the visit of the Philadelphia Chapter of the National Railway Historical Society (NHRS) to the Museum on 12/4/80. Cover printed with logo(tram 31) and title in green ink. Folded so that a paper holding section formed with staples.trams, tramways, btps, nhrs, philadelphia, enthusiasts