Screw for use in safety system for e.g. securing attaching parts at substructure for roof construction, has screw head comprising engagement parts arranged at different distances from middle point of head and provided with different designs

摘要

The screw has a screw shaft, and a screw head (1) comprising engagement parts (2) e.g. projection or prominent cylinder, for a corresponding screw device. The engagement parts are arranged at different distances from a middle point of the screw head, and have two different designs. The engagement parts are asymmetrically distributed over the screw head, and are arranged in a direction of outer periphery of the screw head. The engagement parts are different in its depth and diameter, and the screw head has corresponding markings (3) for the engagement parts. An independent claim is also included for a method for managing customized safety systems.