It is made of structural steel of carbon or alloy material.
Spanner usually in the end of the handle or at both ends of the clamp bolt or nut made of the opening or socket, when the use of the screw along the direction of rotation in the handle applied to the force, the bolt or nut can be turned. Is the use of the lever principle to turn bolts, screws, nuts and other screw fastening bolts or nuts of the openings or holings of the hand tools.
The open end wrench is an important tool for processing, production and maintenance in the mechanical industry.
