Material: Ball lock quick disconnect is made of PBT material, swivel nut is made of stainless steel, worm clamp is made of plastic handle; Easy to connect: Gray barrel disconnect connects 5/16 inch swivel nut, black barrel disconnect connects 3 /16" swivel nut, tightening clamp ensures no leaks when connecting beer tube; Widely Used: Ball Lock Keg Accessory fits most Cornelius Kegs, Pepsi Kegs and 7-UP Cans to dispense craft cocktails from your existing keg , soda and other beverages; GUARANTEE: Quality guaranteed, free refund or replacement for any issues with the ball lock disconnect device. PERA Ball Lock Disconnect - Easy to use and high quality The ball lock connector is designed to connect to a Cornelius barrel quickly and easily. The gray connection is for the gas input on the keg and the black is for the beer output. The black disconnect is on the "OUT" post, which is the liquid post on the beer keg. The gray ball lock is located on the "in" post. The gas column is clearly marked so you can easily distinguish it. Swivel Nut: 1/4 in. (3/16 in.) for black ball lock joint 5/16 in. for gray ball lock joint Tip: Use ball lock break Tightening the clamp when connecting the opener to the beer gas line will prevent leaks. Sometimes the gas hose is difficult to connect, you can put the hose in hot water and then connect the Corny Keg connector.