5/8-18 12pt. Nut (1)

The 5/8-18 12pt. Nut from ARP is a premium fastening component engineered for high-performance applications where precision and reliability are non-negotiable. This chromoly hex nut is designed for use in demanding mechanical assemblies, engine builds, and structural fastening where standard steel fasteners fall short. Whether you're assembling a race engine, building a custom suspension, or securing critical drivetrain components, this nut delivers the strength and durability required for professional-grade work.

Constructed from chromoly steel and finished in black oxide coating, the 5/8-18 12pt. Nut provides superior corrosion resistance and a professional appearance. The 12-point head design offers multiple contact angles for easier installation with both standard and metric wrench sizes, reducing the risk of rounding during fastening. The black oxide finish not only protects against rust and oxidation but also reduces light reflection for a clean, finished look. ARP's manufacturing standards ensure precise thread pitch and dimensional accuracy, guaranteeing proper engagement with 5/8-18 threaded fasteners and consistent clamping force across applications.

This fastener is ideal for engine builders, suspension specialists, and motorsports enthusiasts who demand OEM-plus or competition-grade hardware. The chromoly composition and precision threading make it suitable for high-vibration environments, critical load-bearing connections, and temperature-cycling applications where standard hardware would fail or loosen. Compatible with any 5/8-18 threaded stud or bolt, this nut integrates seamlessly into ARP fastener systems and works alongside OEM or aftermarket components. Single-unit packaging allows you to purchase exactly what your project requires without excess inventory.