A keg coupler is needed to tap any keg. A keg coupler attaches to a CO2 compressed gas tank and then to your keg. it allows the compressed air to flow into the keg, which in turn push out the beer. For your beer to be served properly, it needs to have the correct type of coupler that fits the valve on the keg. Different parts of the world use different valves, so the type of coupler you need will depend on where that specific beer was kegged. The European Sankey “S” System coupler is similar to the American Sankey “D” System. The only difference is that the S-Type Coupler has a ¼” longer probe. S-Type couplers fit beers such as Delirium, Heineken, and Piraat. The S-Type Keg Coupler by U.S. Solid is what you need to start enjoying your delicious beer. Simply connect the coupler to a CO2 source and then screw it onto your keg. Push down on the handle to lock the coupler into place. Starting at low pressure, slowly raise the pressure on the CO2 pressure regulator till it reaches the pressure that is recommended for your keg.