Socket flat head screw, also known as a countersunk bolt, is a type of fastener that is designed to be flush with the surface of the object being fastened. It consists of a cylindrical shaft with threads along its length and a flat, tapered head with a socket or hexagonal drive. The head is designed to be countersunk into the object being fastened, which creates a smooth and flush surface that does not protrude. The socket or hexagonal drive is used with a corresponding tool, such as a hex wrench or socket wrench, to tighten or loosen the screw. Socket flat head screws are commonly made from high-strength materials, such as stainless steel or titanium, which allows them to withstand high stresses and resist corrosion. They are commonly used in applications where a flush and aesthetic finish is desired, such as in furniture, cabinetry, and automotive applications. Socket flat head screws are also used in structural applications where a high level of clamping force is required and the space available is limited.