... -N40/N42/H/SH/T Coating:Zn,Ni,Epoxy Applicationmachine,medicine,package box Sintered NdFeB magnet is much stronger than alnico magnet ... to the ring magnet ,which can be be used in medicine ,machine ,motors ,pakaging box and so on.If you are ... and other requirements. Sintered ring NdFeB magnets used in machine,medicine and etc.