Lock Washer ASME B18.21.1 1999

Shakeproof or Tooth Locking washers have teeth that are twisted to grip and extend radially inward to bite into the bearing surface. They are primarily used for light applications and on soft substrates like aluminium and plastic. They are also used for ground bonding where an object must be electrically bonded to a surface. The teeth of the washer cut through surface oxides, paints or other finishes and provide a conductive path.