Patent ID: 8408855

Claim:
A screw, comprising: a screw head, a screw shaft connected to the screw head, a screw tip at a front end of the screw opposite from the screw head, wherein the screw tip comprises a cutting tip with two front cutting edges and two lateral cutting edges, a screw thread winding around the screw shaft in one direction, the screw thread being configured such that turning the screw advances the screw in a material by engagement of the screw thread in the material, a cutting thread winding around the screw shaft in a direction opposite to the direction of the screw thread, the cutting thread being configured to cut into the material around the screw, wherein the cutting thread has a cutting edge that starts behind the cutting tip and extends only along a part of the screw, beyond which part of the screw only the screw thread surrounds the screw shaft, and wherein a thread pitch of the cutting thread is less than or equal to a thread pitch of the screw thread.