European "S" Keg Tap (Coupler - Sanke)
This is a very common tap for European Beers! 
Some beer styles that this tap works with are: Amstel, Amstel Light Beck's , Beck's Premier Light, Belhaven 80 Shilling, Belhaven Best, Belhaven Best Extra Cold, Belhaven St. Andrews Ale, Belle-Vue Bemish, Cantillon Rose (Belgium), De Koninck Ale (Belgium), Delirium Tremens (Belgium), Dortmunder Union, Double Diamond, Hahn, Heineken, John Courage, Lindeman's.
 

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