The locking methodof NK precision spindle locknuts utilize the elasticity of steel itself, it is compelled to lock with axical locking. This product is designed for bad work surroundings and easy let-off nut. It'sability of locking is 3 times as stronger as traditional locking, this is its advantage.For the locking method of NK because of the miss of assembly,it can not assure the vertical deflection between ground end and threads. Material: DIN C45 or JIS S45CHardness: HRC 28-32Precision: ISO 4HFace Runout: 0.002-0.005