Nut (hardware) Facts for Kids

A nut is a special kind of fastener that has a hole with a spiral groove inside it. Think of it like a tiny tunnel with a twisty path! Nuts are almost always used with a bolt to hold things tightly together. That's why you often hear the phrase "nuts and bolts" – they're a perfect team!

Just like the heads of bolts, nuts are usually shaped like a hexagon (a shape with six sides). This shape is super helpful because it makes it easy for tools like wrenches to grip them tightly and turn them. Nuts also have strength ratings, which tell you how strong they are. For example, a strong nut can hold a bolt very securely without its inside spiral groove getting damaged.

Different Kinds of Nuts
- Acorn Nut
- Flange Nut
- T-nut
- Wing Nut
- Square Nut
- Weld Nut
Images for kids
See also

Different Kinds of Nuts

Left to right: Wing, hex, hex flange, and slab weld nuts.

Left to right: Slotted, square (upper) , T-nut (lower) , cap (or acorn), nylon locking (top and side views), and castellated nuts.

Hexagon nuts.

There are many different types of nuts, each designed for a special job. Here are a few examples:

Acorn Nut

An Acorn nut (also called a cap nut) looks like an acorn because it has a rounded, closed end. This end covers the bolt's threads, making it look neat and protecting the threads from damage or snagging.

Flange Nut

A Flange nut has a wide, flat part (called a flange) at its base. This flange helps spread the pressure over a larger area, which can prevent damage to the material being fastened. It also helps the nut stay in place better.

T-nut

A T-nut is designed to be inserted into wood or other soft materials. It has a wide base with prongs that dig into the material, helping it stay flush and secure when a bolt is tightened into it.

Wing Nut

Wing nut.

A wing nut has two "wings" that stick out, making it easy to turn by hand without needing a wrench. These are great for things you need to tighten or loosen often, like on a bicycle seat or a camera tripod.

Square Nut

Square nuts.

A Square nut is, as the name suggests, square-shaped. They are often used in older furniture or specific types of machinery where a square hole is needed to prevent the nut from turning.

Weld Nut

A Weld nut is a special type of nut that can be welded (permanently attached with heat) to another metal surface. This creates a very strong and lasting connection.