1956 Teamsters Local 600 St. Louis screw-back pin on the original Bastion Bros retail card.

I believe the the pin and the pin-back must have mounted separately on the card when it was brand new, thus the two separate holes in the cardboard.

Approximately 1-1/4" x 1"

The pin shows the detailed front of a truck and trailer

Reads: "TEAMSTERS 600" in raised lettering detail.

The reverse features the Bastian Bros. Co. maker's mark as well as additional union marks.

The Bastian Brothers Company was founded in 1895 in Rochester, NY. The company was initially incorporated as Bastian Bros. Co. and was known for producing jewelry, lapel pins, medallions, paperweights, match safes, pocket knives, ball tap knobs, and tin signs.