Locking washers are designed to secure the relative movement of a properly positioned locknut, so that a bearing and adapter sleeve remains tightly fitted to a shaft or a bearing remains secure against a shaft shoulder. The tab in the bore of the washer engages a keyway in the shaft or slot in the adapter sleeve. There are tabs on the O.d. of the washer that can be bent over into slots on the circumference of the locknut. locking washers are used with locknuts in the kmand kml series as well as for the locknuts with inch dimensions in the N and AN series.