Duff beer is originally a fictional beverage that is consumed on the animated The Simpsons series.

Unfortunately, the origin of this mat is not clear as there are or were several "Duff" beer producers that are not under official trademark. The Klosterbrauerei Eschwege/Germany used to bottle a "Duff" beer with this logo but could not tell me where this mat was produced. 

With the fictional City of "Springfield" beeing situated in the U.S., this item is also listed here. 

If you got more information, please let me know...

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