Thank you to all that responded.....and let me say this. I had NO intention of trying to use one of my Milton air quick couplers that I have UNLESS they were/are approved for propane gas. And the price difference, whatever it may be is a very small price to pay for my personal safety and the safety of others around me. When it comes to combustible gasses, taking shortcuts is a very good way to wake up DEAD! I'm lucky enough to have survived as long as I have.....I ain't takin' no shortcuts in this matter.