GN605-M10-12-B Socket Set Screw Steel Socket set 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. GN 605 socket set screws with full ball point (type A) are used in applications where a ball point contact is required. Indentation on the workpiece is eliminated and the workpiece does not alter its position during clamping.