Is There Such a Thing

I'm not exactly sure what you're doing but you can get double shutoff couplers - shutoffs in both ends. I had a cheapy compressor in my 5er basement and I just mounted it above the pinbox for my 5AB. I teed in and added a second Schrader fitting - one to let air out and the other to leave the compressor quick-coupler connected to and I never disturb it. The compressor valves were leaking a little so I dug thru my toolbox and found a tiny check valve to put in the line between the airbag and the Schrader to the compressor. You can get anything you need from a valve company or pneumatic/hydraulic supplier. Craig