Socket Head Cap Screws
Coarse Thread / Alloy / Plain Finish / Socket (Allen) Drive. Socket head cap screws are also referred to as socket head bolts. The socket head is a hexagonal recessed drive. A hex key or allen wrench is used for tighting and loosening. These bolts are preferred for use in a place where a conventional wrench might not fit. Other popular screws include: license plate screws, sheet metal screws and torx screws.