The plates have a triple coating layer of nickel-copper-nickel which prevents demagnetization, is corrosion-resistant, and won't rust or scratch. 30 x Self-adhesive neodymium magnet plates. HIGH-QUALITY MATERIAL: These magnets are made from industrial-grade neodymium, which won't easily chip/break; They have a Nickel-Copper-Nickel triple coating which is corrosion-resistant, won't rust/scratch and prevents demagnetisation.
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