Hillman 180398 1 1 1 3/8-16 Whiz Lock Nut 100-Pack

Whiz-Lock 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. *.