Description

You know that sinking feeling when you’re tightening down a critical component and the nut starts to back off? It always seems to happen at the worst possible time. This 5/16-18 nylon insert flange nut with its distinctive black cap is designed to stay put once you’ve got it where you want it, thanks to the nylon insert that grips the bolt threads.

What You’re Getting

Nylon insert prevents the nut from loosening due to vibration—no more chasing loose hardware
Built-in flange spreads the load over a wider area, reducing stress on thin materials
Black cap provides weather protection and gives you a visual indicator of proper installation
Fine 5/16-18 thread pitch offers precise adjustment and strong holding power
Self-locking design means you don’t need lock washers or thread locker compound

Built for Real Farm Work

This size nut is commonly found on tractors, mowers, and implements where you need reliable fastening on brackets, guards, and lightweight panels. The flange design makes it perfect for mounting hardware to sheet metal or thin structural components without causing damage or pull-through.

Made to Last

The steel construction handles the constant vibration and temperature changes that come with agricultural work. The nylon insert stays flexible through hot summers and cold winters, maintaining its grip on the threads season after season.

Good to Know

These nylon lock nuts are designed for one-time use—once you remove them, the nylon insert loses some of its gripping power. Always replace with a new nut if you’ve taken one off. Thread it on by hand first to avoid cross-threading, then snug it down with your wrench.