#10-24 Black Zinc Plated Steel Coarse Thread Nylon Insert Lock Nuts (12 pcs.)

Diameter: #10
Diameter 2: 7/16"
Thickness: 15/64"
Material: Steel
Finish: Black Zinc
Driver Type: 3/8" Wrench
Thread Size: 24 (Coarse)
Style: Nylon Insert
Type: Lock Nut

Box of 12.

A lock nut is a nut that resists loosening under vibrations and torque.