Patent ID: 8784023

Claim:
A screw comprising: a head having an underside, the underside having impressions or embossings, the underside facing towards a screw tip and being divided into at least five sectors of the same size, at least three-fifths of the sectors exhibiting an identical pattern of the impressions or embossings and at least one sector is provided with a different pattern of the impressions embossings or else with no impressions or embossings; wherein a first impression or embossing is closest to a second impression or embossing in one direction of rotation, and a third impression or embossing is closest to the second impression or embossing counter to the one direction of rotation, a first angle between the first impression or embossing and the second impression or embossing being different from a second angle between the second impression or embossing and the third impression or embossing, wherein the first angle is twice as large as the second angle.