DIN 980M prevailing torque nut metal insert

a). Prevailing torque type hexagon nuts feature a design where increased friction within the threads prevents the nut from loosening on its own. This friction is generated by the prevailing torque element integrated into the nut, which induces axial and/or radial clamping in the bolted connection.

b). DIN 980 (Type M) Two-piece metal nuts are nuts in which enhanced friction is achieved by inserting an additional metal element into the prevailing torque mechanism of the nut. However, this type does not have full loadability.