The ribs cause the supporting surface to deform and then harden, thus increasing the loosening torque of the screw.

• More efficient loosening pro­tection than tooth lock washers or the like.
• Reduced number of assembly components.
• Improved feeding at the assembly compared to screws combined with washers.
• No formation of chips in mounting process.
• Reduced notching in the component.
• Reduced costs for the assembly in total.