Fasteners are hardware devices that are used to join two or more objects together. They are a key component in many different types of products and structures, including buildings, vehicles, machinery, and consumer products.

Fasteners come in many different forms, including bolts, screws, nuts, washers, and clips. They are typically made from a variety of materials, such as steel, stainless steel, aluminum, brass, or plastic, depending on the application and the required strength and corrosion resistance.

The choice of fastener depends on the specific application and the requirements for the joint. For example, a bolt may be used in a high-stress application where a strong, durable joint is required, while a screw may be used in a lower-stress application where a secure, yet removable joint is needed.

Fasteners are typically specified by their size, thread pitch, and thread diameter, as well as their material and surface finish. It is important to select the right type of fastener for a particular application to ensure a safe, reliable, and long-lasting joint.