A socket cap screw is a type of cap screw with a hexagonal recessed drive. A hex key is required to tighten or loosen a socket screw. Socket screws are commonly used in assemblies that do not provide sufficient clearance for a conventional wrench or socket. As the industrys most trusted fastener supplier, Midwest Fastener has earned a reputation for delivering a complete line of high-quality bulk and construction fasteners to meet consumer needs. Contractors and DIYers alike have come to depend on Midwest Fastener to provide them with the critical parts and fasteners necessary to ensure the success of their projects.