Magnetic closures for containers

I recently saw some phase boxes that were held closed by two strips of
magnetic tape. They looked neat, effective, and simple to make. However,
I've since been told that the adhesive on the tape yellows and migrates,
the magnets have to be covered, and the magnetism eventually wears off.
Has anyone used this tape on phase boxes and portfolios, and what has
your experience been?

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                  Conservation DistList Instance 7:83
                  Distributed: Wednesday, May 18, 1994
                        Message Id: cdl-7-83-006
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