Most of the applications I have, I'd go with
farm experience rather than a web site that
claims this or that.

Do you ever stack a lock washer and flat
washer? And, how does that turn out?
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Christopher A. Young
Learn more about Jesus
www.lds.org
..
..
"dpb" wrote in message ...

I don't have any scientific evidence but 50+
yr practical use on farm indicates to me they
serve a useful purpose.

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