Abstract: A plurality of anchoring members are threaded onto the shaft of the fastener. These anchoring members include an annular body and a spacer. The anchoring members are held between an abutment of the shaft and a locking section thereof fixed against an axial displacement thereon. The anchoring members are present as structural members which are separate from the shaft and are merely threaded onto the shaft. It is accordingly possible to use a large number of variously designed anchoring members together with only one shape of the shaft, which reduces considerably the costs of the production and increases the universality of the fastener. Specifically the shaft and the anchoring members may be made of a metal such that the fastener can display in comparison with plastic fasteners a much higher rigidity.

Abstract: A self-drilling screw includes an axially extending screw shank with a leading end and a trailing end. A drill bit is secured to and extends axially outwardly from the leading end of the screw shank. At least one wing extends laterally outwardly from the drill bit transversely of the axial direction of the screw shank and spaced from the cutting edge at the leading end of the drill bit. The wing has a cutting edge facing toward the leading end of the drill bit. The wing extends outwardly beyond the outside diameter of the screw shank and forms an enlarged bore through which the shank can pass without contact with the surface of the larger bore. Each wing has a break-off groove or notch so that it can separate from the drill bit.

Abstract: A self-tapping screw whose stainless steel shank has a slotted free end in which a plate-shaped, carbide drill bit is fastened, the bit being dimensioned and arranged to drill a hole smaller than the major diameter of the tapping threads.