Product Advantages:       1, Permanent ring magnet size: 0-150mm 2, Magnetizing Direction: Radial or Thickness 3, Assembling: Permanent ring magnet can be assembled with steel shell, disc or plastic cover for device. 4, Unusual plating: Any special coating you may want, no problem! Even unusual such as black zinc. 5, Sample: Permanent ring magnet quick finished around 5 days, and ship free. 6, FEA: magnetism FEA analysis or simulation can be supplied.  7, Physical detection: Report of physical detection offered to client each order.