Deep sockets made of a special alloy steel.
The socket walls are made thin for easy access to nuts and bolts set in narrow spots.
The nominal size of the socket is determined by measuring the opening of the socket, not the bolt size.
Only supplied in a 12.7 mm sized square drive attachment.
12 point sockets and sockets in metric sizes are available.
A hole is located at the top of the socket for use with a cross bar.