KEG COUPLER: A keg coupler is what allows the beer to flow from the keg; It attaches to a CO2 compressed gas line and lets compressed air to enter the keg and push out the beer KEG: Kegs are made differently around the world; Knowing where your beer was kegged will tell what kind of keg coupler you will need A-TYPE: The A-Type keg coupler will fit most german kegs; Some popular german kegs that use the A- Type coupler include Hacker Phsorr, Hoegaarde, and Warsteiner CO2 KEG TAP: A CO2 keg tap uses CO2 to push the beer out of the keg; Compressed CO2 is pushed into the keg to pressurize it; By pressurizing the keg, you allow the beer to flow out through the top of the keg WARRANTY: All U.S. Solid products are backed by a one year satisfaction guarantee; If you have any problems or concerns, please contact our customer support team and they'll be happy to assist you