1" dia. enamel on brass stud with threaded post and screw cap reverse both carrying the name of the maker St. Louis Button Co. In addition to the group's initials and the designation "Press" additional text reads "Dec. 3-4-5 1941/Jacksonville, Fla." This group was formed in 1901 as a reaction to strife going on between the National League and the American League. The purpose of the organization was to govern minor league baseball in North America. In 1931 major league teams began affiliation with minor league teams and Branch Rickie, president of the St. Louis Cardinals, was the architect of the system which still exists today. Trivial reverse tarnish. Essentially Mint as made. Only example we've seen.