The Department issued this 4-cent stamp on October 15, 1960, through the Detroit, Michigan, post office, featuring the theme "Wheels of Freedom." The stamp honored the automotive industry and issued in connection with the National Automobile Show in Detroit from October 15 - 23, 1960.
Designed by Arnold J. Copeland, the stamp was printed by the rotary process, electric-eye perforated, and issued in panes of fifty stamps each. An initial printing of 120 million stamps was authorized.
Postal Bulletin (September 8, 1960).