#4-40 Zinc Grade 2 Nylon Insert Lock Nuts (100 pcs.)

Diameter: #4
Diameter 2: 9/32"
Thickness: 5/32"
Material: Steel
Finish: Zinc
Driver Type: 1/4" Wrench
Thread Size: 40 (Coarse)
Hardness: Grade 2
Style: Nylon Insert
Type: Lock Nut

Box of 100.

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