2.25" with rim reading "Legion Post 504." Tin-covered reverse with bar pin. Curl reads "Cruver Mfg. Co. Chicago." This city west of Chicago was once home to six windmill manufacturers with the Challange Company and Appleton Company the largest. By the 1890s, Batavia was known as the "Windmill City." In the 1960s the nations' most powerful particle accelerator (Fermi Laboratory) was built here and the town became "The City Of Energy." Hake book Collectible Pin-Back Buttons photo example Farm Equipment Section #169. Surface has dozen tiny scattered raised cello dots that catch reflected light. Comes with Hake's COA. Exc., displays Mint. Only example known to us. Rare.