#4 x 7/64" x 9/32" 18-8 Stainless Steel Internal Tooth Lock Washers

Diameter: 7/64"
Diameter 2: 9/32"
Thickness: 1/32"
Material: Stainless Steel
Hardness: 18-8
Nominal Size: #4
Style: Internal Tooth
Type: Lock Washer
Application: Smaller head screws

Box of 50.

The purpose for a lock washer is to prevent threaded fasteners from loosening by creating friction between the fastener and the mounting surface.