Fixing the test ring is analogous to the installation situation (Orientation and angle in the vehicle ): Fixing the original attachment points The screw cases are to be run analogously to the original screwed connection. A tightening case is defined by: Diameter, length of shaft,length of thread, thread type, strength class, layer, head shape and material of the screw. In addition, the material, the coating and the number of clamping device analog must be carried out in the original screwing.