A nut driver consists of a handle and a socket or hollow shaft at the end. The socket is sized to fit a specific nut or bolt head. It typically has a hexagonal shape to accommodate hex nuts and bolts, although other shapes like square or double-D may be used for specialized applications. Nut drivers are available in various sizes, ranging from small drivers used for tiny nuts and bolts to larger ones for heavy-duty applications. Some nut drivers have magnetic sockets to hold the fasteners in place, providing convenience and preventing them from falling.