- Hex Acorn Nut - Looks like a cap nut but with a taller dome to prevent contact with the external threads.
- Hex Cap Nut - This nut has a cap. The bolt needs to be the correct length in order to make a tight fight. It also gives a clean appearance to the nut.
- Hex Flange Nut - This nut has it's own washer. Once tightened, the serrated bottom of the washer will resist loosening caused by vibration.
- Hex Finished Nut - Also known as a finished full. It is used with a bolt to fasten materials together.
- Hex Heavy Nut - This is just what the name says, it's a heavy "hex nut".
- Hex Finished Coupling Nut - Couplers are just a long nut. They are used to connect two fasteners together - threaded rods or bolts.
- Hex Heavy Coupling Nut
- Hex Machine Screw Nut - This nut is used with machine screws 1/4" and under.
- Hex Finished Jam Nut - A thinner version of a hex nut.
- Hex Heavy Jam Nut
- Hex Jam Nylon Lock Nut - A thinner version of a hex lock nut nylon insert.
- Hex Lock Nut Nylon Insert - To resist loosening from vibration, this nut has a nylon material at the top of the nut.
- Hex K-Lock Nut - Has a free-spinning external tooth-lock washer attached to the nut.
- Prevailing Torque Lock Nut - This is meant to be a non-reversible nut. If you do try to remove the nut, it may damage the threads, hence the name lock nut. All lock nuts are non-reversible.
- Hex High Crown Cap Nut
- Hex Low Crown Cap Nut
- Hex Slotted Castle Nut - Castle nuts are made to be used with a cotter pin. With this nut, the cotter pin can be bent within the boundary of the nut. A hole is drilled in the shank of a fastener for the cotter pin. Once inserting the cotter pin, the nut will be prevented from loosening.
- Hex Slotted Heavy Nut - This is the same as a castle nut, but the cotter pin is bent around the nut.
- Square Nut - Square nuts can be used in a channel where it is hard to get a wrench. Being square, it can lock itself next to the channel. It can also be welded in place. This nut used to be quite common but has been replaced by the hex nut in most cases.
- Square Heavy Nut
- Square Machine Screw Nut
- T-Nut - This nut is designed to pull against wood or material softer than metal without leaving marks like other nuts might.
- Two-way Reversible Lock Nut - These are reversible nuts that can be used on either side, but removing these nuts usually destroys them.
- Wing Nut - They can be turned by hand and do not necessarily need tools.
- ASTM Standards
- ASTM A563 - Standard Specification for Carbon and Alloy Steel Nuts
- ASTM F594 - Standard Specification for Stainless Steel Nuts