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Multipole Neodymium Super Ring Magnet – Arbor Scientific
Strong Hand Tools - Str-7089 , Heavy Duty, Adjust-O Magnet Square, On/Off Switches, Pull Force: 160 lbs, 6" x 5-1/8" x 1-3/8", MSA48-HD: Magnetic Sweepers: Amazon.com: Tools & Home Improvement