MLB Subway Sign with Field Dirt Chicago White Sox. This vintage-style Subway Sign is a must-have for any Chicago White Sox fan! Rather than showing the stops along a subway line, this unique sign details stops along the White Sox' history. Comes in a handsome frame, and measures 1" Thick. Features dirt from U.S. Cellular Field, authenticated by the MLB! Guaranteed authentic by Steiner Sports. Materials: Mica, Plexi, Glass, Dirt.