With a nylon insert that grips your threaded shaft or spindle without damaging its threads, these locknuts—also called shaft nuts—hold bearings, bushings, gears, and pulleys prone to vibration tightly in place. They come as one piece, so you can easily clamp them onto your shaft or spindle. But, since they aren’t made entirely of metal, they don’t stand up to heat as well as all-metal locknuts. Slots in their sides mean you can tighten and loosen them with a spanner wrench or spanner socket. Their face is also chamfered to help keep the size and weight of your assembly at a minimum. All meet international standards for bearing locknut dimensions.

With Loctite® adhesive already on the threads, these inserts won’t back out or vibrate loose. The adhesive reaches full strength after 72 hours. Unlike helical inserts, you can install them with a standard drill and tap. However, thread-locking inserts are difficult to remove and reuse.

After drilling and tapping your hole, install inserts with a wrench or an installation bit. To use a wrench, thread an insert and two hex nuts onto a bolt. Then, grip and turn the top nut to drive into the hole. For slotted inserts, you can drive with a slotted screwdriver instead.

Used in pairs or with another bearing nut, these thin-profile nuts—often called shaft nuts—hold bearings, bushings, pulleys, and gears in place on your threaded shaft or spindle. Threading two nuts tightly against each other makes it harder for vibration to loosen your assembly than if you used only one nut. For the nut closer to the bearing, position the stepped face towards the bearing. These thin-profile nuts have holes on the side, so you can tighten and loosen them with a pin spanner wrench. All meet DIN 1816, an international standard for bearing locknut dimensions.