1/4"-20 Polished 18-8 Stainless Steel Coarse Thread Nylon Insert Lock Nuts

Diameter: 1/4"
Diameter 2: 1/2"
Thickness: 5/16"
Material: Stainless Steel
Finish: Polished
Driver Type: 7/16" Wrench
Thread Size: 20 (Coarse)
Hardness: 18-8
Style: Nylon Insert
Type: Lock Nut

Box of 8.

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