The Hillman Group 300027 Hillman Split Lock Washers 7/16" Zinc Plated Steel 50 / Box, 50 Pack, No Color
This split lock washer provides a circular bearing surface with offset split ends which help bite into the mating material to provide a locking feature when tightened beneath a nut. It is round with a hole in the center and can be used where loosening from corrosion or vibration is a concern. Lock washers are commonly used in any application using a bolt where two pieces are being drawn together.