Safety wire
![Safety wiring of two pairs of drilled bolt-heads wired one-to-the-other](/Images/godic/202501/28/Safety_wiring_-_Jaguar_rear_subframe2148.jpg")
![A moused shackle](/Images/godic/202501/28/Moused_shackle2148.gif")
Safety wire or locking-wire is a type of positive locking device that prevents fasteners from loosening or falling out due to vibration and other forces. The presence of safety wiring may also serve to indicate that the fasteners have been properly tightened.