Abstract: A self-tapping screw having a boring part and a threaded shaft for fixing a panel-type object to a preferably metallic substructure is provided. The screw is configured in such a way that it produces a through hole in the panel type object, said hole accommodating the shaft with a degree of play and so that it produces a bore in the substructure into which the thread on the shaft cuts a counter-thread. The boring part includes a boring tip that is located eccentrically in relation to the longitudinal axis of the screw. The tip centers the screw during the positioning operation in such a way that the boring part executes a circular displacement about the boring tip, which expands the through hole to the desired size, whereas the bore in the substructure is produced with the diameter of the boring part.

Abstract: An anchor device comprising an elongated insert which has a lower end, an upper end, and a plurality of rib members extending radially therefrom, each of said rib members having a radial width which increases gradually in a direction from said lower end to said upper end of said elongated insert; an attachment seat integrally connected to said upper end of said insert and upper edges of said rib members; a metal shaft embedded longitudinally in said elongated insert, said metal shaft having an upper end which is embedded in said attachment seat, and a lower end which extends out of said lower end of said insert; and wherein said lower end of said metal shaft is tapered.