1.shape:stick,black,ring,disc and so on. 2,Certificate:ISO9001:2008 3,Grade:N35-n52,etc 4, ... ,N28AH-N30AH;4) Shape: ring, block, disc, bar and so on;5) Size: according to customers' request;6) Coating: Ni, Zn ... , gold, copper, epoxy and so on;7) Application: sensors, motors, rotors, wind turbines, wind generators, loudspeakers ...