Material: sintered Neodymium-Iron-Boron magnets; Grade options: From N35 to N52; Coating options: NiCuNi; Zinc; black epoxy; phosphating; Neodymium magnets or rare earth magnets with rubber coating, which prevents the magnets from scratching the metal surfaces; Magnets with plastic cases are office used in the office as memo board magnets; Countersunk hole round base magnets with pulling force from 10 lbs to 350 lbs ; …