I'm using these magnets to attach a wall mailbox to a steel door. They are perfect. Very strong but the rubber prevents scratches to the paint. The rubber barrier does diminish the pull force of the magnets (they're still very strong, but much less than uncoated magnets I have of a similar size), but that's not a problem for me. I imagine most people who want rubber coated magnets are prioritizing the scratch prevention to pull force. These are still very strong, and are large magnets sized such that the reduction in force is compensated by their larger size. The hardware makes them attach very securely.
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