The working function mechanism of Steel Expansion Anchors the systems are threaded stud, stamped sleeve tube, shells, or wedge bolt assembled which is achieved by a tapered cone nut, nail, screw ,threaded stud or bolt depending on the used styles of expansion anchors. The compression power of the expansion system against the wall drilled hole the anchor to transfer the load to the basis material.They are expanded to fix the objects in the concrete, masonry, brick, stone or the solid wall.