... shape 3.Stable performance 4.Good corrosion resistance Ring magnets for speaker material: sintered NdFeB magnet;rare earth permanent magnetsshape: ... magnets, and also include special magnetic-bar, magnet with iron-shell, adding water-proof pvc film magnet, and magnet ... RoHS certified. 5) Use of magnetOur magnets are used for motor speaker, hardware, package, cabinet lock ,door lock and health ...