... OD170mm Ring shape with hole High coercive forceNeodymium Ring Magnet with N35,N38,N40,N42,N45,N48,N50, ... .Application for NdFeB magnet:Magnetic separator, Sensors, Wind generators,Vibration motors,DC motors, Servo motors,Linear motors,VCM,MRI, ... Loudspeakers,Linear actuators,drives,toys,bags,household appliances,microphone parts,transmission equipments...Features of NdFeB magnet :Neodymium magnets ...