Another option is the Light Coupling 15 Series from Pisco which also incorporates a quick fitting and has a flow rate of .81Cv.
The Pisco Coupling Module can be used not only to extend the coupling but also in combination with the Main Block. The number of blocks in the Coupling Module can be chosen for your application. The socket comes with a stop mechanism that stops air simultaneously with the removal of the plug.
Contact DAS Services, Inc. for anything you might need regarding the Pisco Coupling series.