1/2" x 7/8" x 39/64" 18-8 Stainless Steel External Tooth Lock Washers

Diameter: 1/2"
Diameter 2: 7/8"
Thickness: 5/64"
Material: Stainless Steel
Hardness: 18-8
Style: External Tooth
Type: Lock Washer
Application: Round|pan|or binding head
Diameter 3: 5/8"

Box of 10.

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