This white, beverage out quick disconnect comes with a barb for attaching to a gas line, and it's made by CM Becker so you know it is high quality.
The flare measures 1/4 inch
Note: Sometiems ball lock fittings can be difficult to get fully seated on a Cornelius keg. We recommend using a quick spray of sanitizer solution to act as a lubricant and giving it a few twists while applying the ball lock.