#10 x 3/16" x 27/64" Chrome Plated Grade 8 Steel Internal Tooth Lock Washers

Diameter: 3/16"
Diameter 2: 27/64"
Thickness: 3/64"
Material: Steel
Finish: Chrome
Hardness: Grade 8
Nominal Size: 3/16" (#10)
Style: Internal Tooth
Type: Lock Washer
Application: Smaller head screws

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.