3/4" with "Medallic Art Co." on reverse in tiny raised letters. Our research indicates this is likely from 1916 as a billboard, used in Colorado, featured a woman standing next to a hat labeled 50/50 and paid for by the National Woman's Party. Pin features a man and a woman holding up a globe. Very minor tarnishing contained mostly to edges and a small spot on the globe. Fine. First we've seen in five decades.