What is a Convex Nut?

Convex and Concave nuts

A convex nut is a protruded locknut that has been machined eccentrically. It is used in combination with a concave nut to make up the HARDLOCK Nut (two nut system). Because there are no deformations or machining of the threads, convex nuts have the same mechanical properties as a regular hexagon nut. The convex nut has the same height as a regular nut and can be torqued the same as a regular nut. The eccentric protruding section acts as a wedge, combining the two nuts (convex and concave) eliminates the gap (play) between the screws threads.

Convex nut
HARDLOCK installed on bolt