Indio Bravo wrote:
....

Thanks, I can see this for the sliding washer. But what about the same
washer being compressed against the flange underneath the sink basket.
It looks good to see the flat portion seat against the underside of
the flange but shouldn't it be the other way around? Is the
compression force being applied on the flat side in both cases, and
not on the tapered side?

You talking waste or supply lines, here????

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