GN 606 socket head cap screws with full ball point (type A) are used in applications where a ball point contact is required. The flat faced moveable ball (type B) allows the clamping or supporting of non-parallel surfaces. Indentation on the workpiece is eliminated and the workpiece does not alter its position during clamping. Socket head cap screws with safety twist ball (types V and VR) are designed so the flat faced ball cannot twist more than a maximum of 9 degrees. This allows full clamping of the flat faced ball at all times.