Socket Head Cap Screw is a type of fastener with a cylindrical head that features a socket or recess in which a drive tool can be inserted. It is primarily driven by hex tools (Allen wrenches), but can also be used with power tool drivers.

Its hex drive allows for easy and precise torque application. It is ideal when access to tight spaces is limited and where bolts or screws would normally protrude. It is often installed with its head recessed within a counterbore, leaving it flush with the surface of the component it is fastening to. This eliminates any protrusions that could catch on or get in the way of other tools, and produces a clean appearance.

These are available in a wide range of sizes and materials, catering to diverse industries and environmental conditions. They can be manufactured from a variety of metals, including alloy and stainless steels, and may undergo various heat treatments to improve their strength, hardness, corrosion resistance, or other properties. They are often finished, coated, or plated, to provide additional strength, durability, and visual appeal.

This is an important category of fasteners that are commonly utilized in a broad range of industrial applications. They are particularly popular in construction, where they are often employed to anchor structural components and to support heavy loads. They are also utilized in manufacturing and electronics, where they are primarily used to create assemblies or to attach machine parts together.