This is a vintage Hamm's beer keychain celebrating its 100 year anniversary in 1965. It is made of metal, possibly brass or bronze. The medallion measures a little less than 1.25" in diameter. The front reads "Three generations of brewing excellence 1865 - 1965." The center has the iconic Hamm's crown / pine tree logo and says "Hamm's 100 years." The back reads; "Return postage guaranteed deposit in any mailbox. Theo Hamm Brewing Co. 720 Payne Ave., St. Paul, Minn." It is also numbered in the center. This one is numbered "027147." The medallion has the original chain and clasp which still works. 

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