The the metal bone screw belongs to the third category product of the surgical implanting substance. It is divided into two categories, i.e. thin screw thread ( HA) and deep screw thread ( HB) . According to using place of the product, it is further divided into full screw thread, half-screw thread, normal type and self-tapping type. This product is mainly used for internal fixation of the bone fracture. During using, normally it is in matched use with the metallic bone connecting plate or bent steel plate of the same material for curing of the bone fracture.