Why not just make an inflator out of a regular kitchen trash bag and a short piece of light thin hose or the inflator hose that came with one of your pads? Holds about 4-6 lungs full. Whatever. Go ahead and puff away. Turn yourself blue.
I live in a moist humid environment. I had a Stephenson warmlite downmat pad from @ 1976 lose the integrity of the waterproof/airproof urethane coating evidently due to mold attacking the adhesives. Who knows for sure?
And I’ve got some thermarests from maybe even the Nixon Admin there David ;) I think they all still work. Maybe the answer to delamination is to stick with thermarest.
Meantime it’s yes sir yes sir 3 bags full (or maybe 4) to inflate an xtherm with my sub one ounce kitchen trash bag inflator. Why in the world would I try to blow it up by mouth?

