Bolts are designed for installation on equipment by turning nuts
using a tool such as a spanner. As you turn the nut, it applies a clamping force while the bolt pins the joint tightly and prevents it from shear forces that push sideways. Therefore, you cannot use a bolt without a nut. It must have a nut; otherwise, it will not fasten tightly.
Bolts feature a cylindrical body with a flat, curved, or sunken top. Along the length of the shaft are screw threads. The nuts feature internal threads ingrained in a way that matches the groves on the bolt. For a tight grip, you can use washers; these accessories also prevent crushing.
Bolts come in a wide variety of sizes and tensile strengths. An array of materials including, steel, copper, and aluminum, are used in their manufacture. Other elements include alloys of these and other metals. Bolts are coated with zinc and other anti-corrosion properties.