Most steel structures are fastened together on site by nuts and bolts. These come in a variety of sizes, from 6mm to 100mm in diameter.

A fastener is a hardware device that mechanically joins or affixes two or more objects together..
Fasteners can also be used to close a container such as a bag, a box, or an envelope; or they may involve keeping together the sides of an opening of flexible material, attaching a lid to a container, etc.

An anchor bolt is used to attach objects or structures to concrete. There are many types of anchor bolts, consisting of designs that are mostly proprietary to the manufacturing companies. All consist of a threaded end, to which a nut and washer can be attached for the external load. Anchor bolts are extensively used on all types of projects, from standard buildings to dams and nuclear power plants. They can also be used to firmly affix embed plates to a concrete foundation when used with a structural steel element.

Stainless steel does not readily corrode, rust or stain with water as ordinary steel does, but despite the name it is not fully stain-proof, most notably under low-oxygen, high-salinity, or poor-circulation environments.[2] There are different grades and surface finishes of stainless steel to suit the environment the alloy must endure. Stainless steel is used where both the properties of steel and resistance to corrosion are required.

A bolt that is adjusted to a carefully controlled tension by means of a calibrated torsion wrench; used in place of a rivet. Also known as a high-tensile bolt.

(socket head cap screw) – metric thread.

A bolt with its threaded end projecting above the foundation and secured so as to hold down a steel structure against wind loads or machinery against its vibration.