Choose from our selection of medium-strength steel locknuts, low-strength steel locknuts, metric medium-strength steel locknuts, and more. Same and Next Day Delivery.

Choose from our selection of slot nuts, including T-slotted framing fasteners, T-slot nuts, and more. Same and Next Day Delivery.

Shop through a wide selection of Slotted Nuts at Amazon.com. Free shipping and free returns on Prime eligible items.

Choose from our selection of slotted hex nuts, including medium-strength steel hex nuts, stainless steel hex nuts, and more. Same and Next Day Delivery.

Slotted nuts, also referred to as slotted hex nuts or castellated nuts, have grooved heads with holes that allow for insertion of pins, which will lock the nut in place. Slotted hex nuts are commonly used in automotive assemblies or machine settings to ensure that the components are staying in place, or for general purpose fastening and locking.

Slotted nuts are just that—hex nuts with six large slots 60° apart in the top center of each flat (side). Their strength is said to be 80% of "full thickness nuts of the same size, style and grade."

Slotted Nuts are used in applications where vibration or motion might undo the locknut. Both a Castle Nut and Slotted Nut look similar, and can often be used interchangeably because they have almost identical dimensions.

A low carbon steel for general use. Unplated finish.

Slotted hex nuts have opposing slots cut into the end of the opposite side of the bearing surface. Slots are used for the insertion of a safety wire or cotter pin, creating a secure hold that prevents loosening or unscrewing. Need help finding the round slotted nut fasteners you need?

A slotted nut, also known as a castellated nut, is a hex nut with opposed slots cut into the top of the nut through the centers of the flats. The slots are on the end opposite the bearing face. The slots are for the insertion of a cotter pin to secure the nut when used with a drilled shank fastener.