Sockets
When compared to open-end wrenches, all-purpose sockets have an enclosed head that can apply more torque and is less prone to fall off bolts. To loosen or tighten fasteners, these sockets require drive tools such as ratchets or breaker bars to spin them. To suit SAE or metric fasteners, sockets are available in SAE (inch) or metric sizes. Square drives are included with drive tools, and they fit into sockets with the same size drive end.