... the coating, shape, sizeSurface treatment: Ni, Zn, Epoxy, Gold, Silver, Tin, Ni+Cu+Ni and Cr3+ZnSize available: 0.5-200mmShape ... : Block, Square, Disc, Cylinder, Ring, Rod, Bar, Stick, Tile, Fan, Ball3. Competitive, Reliable, Reasonable Price ... factory and cooperate with esteemed OEM!! round disc permanent magnets/ring magnets/neodymium magnets