Anagram wrote:
dpb wrote in :

It's just a standard compression fitting. The flare is a compression
sleeve; the tubing will get compressed slightly and then flare some

Thanks for the explanation. That makes it much clearer.

Can I re-use the compression threads as a non-compression kind of adaptor?
Such as if I put teflon tape on the compression threads, and screw some
kind of adaptor onto them, so the water will go through the inside, with
nothing compressed?

No.

Compression fitting threads aren't tapered like NPT and are not designed
to be leak-tight. The threads do nothing in a compression fitting
except apply the force to pull the compression sleeve into the fitting
to make the watertight connection.

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