serrated washers
Rim washers protect bolts, nuts and screws from vibrations. Areas of application are mechanics, electrical engineering or electronics.
Form A has an external toothing, whereby each individual tooth makes permanent contact with the connected surface. The surface should be flat.
Form J works with an internal gear and is used when the surface of the bolt or bolt head is not flat.
Form V also has an external gear and can be used for a 90° bevel head. This form should also be used if the surface of the cap is irregular.