7/16"-14 Black Phosphate Grade 2 Nylon Insert Lock Nuts LNS-415 (253 pcs.)

Diameter: 7/16"
Diameter 2: 23/32"
Thickness: 15/32"
Material: Steel
Finish: Black Phosphate
Driver Type: 11/16" Wrench
Thread Size: 14 (Coarse)
Hardness: Grade 2
Style: Nylon Insert
Type: Lock Nut

Box of 253.

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