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These powerful 2" diameter X 1/2" thick NdFeB disks are brand new, Licensed NdFeB, Grade 35 material. They come Nickel plated to help prevent chipping and corrosion. Actual field density measured at the surface of one of these magnets is around 3500 Gauss. Br Max (the maximum field density which can be generated by this material) is 12,100 Gauss (this is considered to be the "Gauss Rating"). One of these magnets, under ideal circumstances can lift around 200 pounds of Iron! [...]
These magnets are serious tools and somewhat dangerous if mishandled! Due to their size and dimensions, these magnets are larger than necessary for most applications. These are popular for underwater salvage, and some lifting applications - however, it should be noted, that a heavy, unbalanced load when lifted with magnets can easily break loose! Never use magnets for lifting unless you don't care that the load might unexpectadly break loose!