The U.S. Solid Keg Coupler will give you the best pour of beer. A keg coupler is needed to serve beer from a keg.The coupler is what allows the beer to flow out of the top of the keg. Using CO2 the keg coupler will pressurize the keg and push the beer out. The type of coupler you need will all depend on where your beer was kegged. The “A” System coupler fits most German beers such as Hacker Phsorr, Hoegaarde, and Warsteiner. To install a coupler to your keg, you will need a CO2 tank. Take the CO2 tank and connect it to the nipple side of the coupler. Screw the coupler onto the keg and push the handle down to lock it in place. Turn the CO2 tank on and slowly raise the pressure till you reach the recommended pressure to serve the beer in your keg. The U.S. Solid beer coupler will ensure that you have great tasting beer every time.