1.5” from early 1900s featuring tin rim and unusual all tin reverse with small opening at top holding a vertical stickpin with a small tin cut-out below to hold the pin point in position. Back stamp of rarely seen firm “Louis F. Dow Co. St. Paul.” Front has serial number “2124” with text “Find Your Duplicate And Come To Our Booth/The 20th Century Machinery Co./Manufacturers Of Bottle Washing Machinery/Milwaukee Wis.” Exc. and the only example we’ve seen. From the Morry Greener Collection.