Mark:

Thanks. I read that thread, and the related others I could find, before posting and it does a great job explaining how to put everything together. Unless I missed something, it still does not clarify just how much air volume will go thru the quick disconnect fittings.

I did receive an off-line reply from a friend I met diving this past year and he said he took his QC6 to 100m and breathed using that line as hard as he could and it delivered enough air. I can do the math and see how much gas the system was providing, and that helps a lot. Definately, the QC6 allows enough gas to pass to operate a second stage in real life at 100m. Thanks for that data.

Now, has anyone done the same thing any deeper than that?

Hopefully, you see my question. If you are going to design a life-support system, emergency or otherwise, shouldn't you be able to put it together with pieces based on their specs?

Sorry if I'm being a pain.

Bill