1.75” with no maker name or back paper. About 20% of the silver flashing is off the reverse but otherwise condition is NM displaying Mint. Additional text on the button is “Organized-August-9-1911.” This military post was established in Cheyenne, Wyoming in 1867. By the turn of the 20th century it was one of the largest calvary bases in the United States. Button was likely issued in 1912 in support of Roosevelt’s Progressive Party election campaign. Rare.