Often confused with hex head socket cap screw, the button head socket cap screw is a different fastener that is used in applications where there is limited space and the application calls for a flush appearance. Also known as a domed cap screw or allen head cap screw, the button screw features a low profile and wide load-bearing surface that resist looseness.

Like other socket head screw types, the button socket cap screw is threaded and can be tightened with a wrench or socket. The difference is that the head on a button screw is smaller than a socket head and can be turned with a hex key instead of a wrench. This allows the screw to be tightened to higher torque specifications than other fasteners, but with a smaller head that can fit into small spaces without snagging on equipment or other materials in the area.

Hex head cap screws, or hex bolts as they are sometimes called, feature a hexagonal center recess that fits a hex wrench for turning and are typically used with a washer and hex nut assembly or in a tapped hole. The hex-shaped head provides greater grip than other screw heads and is capable of creating a compressive force that prevents rotational movement. Hex head cap screws can be driven by hand or with a power tool, but the deep hex recess and thick side walls make them better suited for wrenching than most other screw types.

Button head socket caps, or domed caps, have a rounded, low-profile head with a large bearing surface that allows them to hold more weight than other head styles and offers a finished look for the final product. The low-profile head is countersunk into the surface, so it sits flat with no protrusions that could catch on clothing or other materials when they are in use. Button screw heads are available in a variety of sizes and materials to suit a range of applications.

Both the cap screw and the button head cap screw offer advantages in their own ways, but the final choice will come down to the specific requirements of each project and the desired appearance of the final product. Cap screws are better suited for strength and durability applications, while the button head cap screw can be used in areas with limited space and will provide a more polished finish. Ultimately, the type of screw that you choose should be determined by the specific needs of your application, so it is important to consider factors like strength, durability, and corrosion resistance when making your selection. Choosing the right fastener will ensure that your project is completed properly and safely.