Two Types of The Locknut

Lock nut has the holes(usually has 2 holes, with the angle of 90 degrees distributed on outer surface of nut) pass through the outer surface and the inside nut thread surface, which allow the countersunk screws of small diameters, and the purpose is to exert the force to threads in a radial direction to prevent the locking nut loosened.

1. Screwing the same two nuts on a bolt, and to attach a tightening torque between two nuts, so make the bolt reliable connection.

2. Dedicated locknut, it needs to be used together with a lock washer. Dedicated locknut is not hex nuts, but a middle-round nut, the nut circumference opened a three, four, six or eight notches (varies depended on the nut size and manufacturer product series ), which are the focus of tightening tools, as well as the snaps washer locked into.