Hillman 180397 Whiz Lock Nut, Coarse Thread, Steel, Zinc-Plated

Whiz-Lock, one-piece all-metal, free spinning nuts have been proven to overcome vibration and a variety of other forces. The underside or bearing surface of the fastener, has a series of spiraling serrations or teeth, to provide a locking, reliable hold. The application of this nut is as easy as spinning it on. They simply spin on to mating thread and lock when seated per medium of toothed flange.