Description
Premium Hex Head Cap Screws Grade 8 Steel Plain (USA Made) 5/8-18 x 6-1/2 are engineered for heavy-duty fastening in automotive, industrial, and machinery applications. Crafted in the USA from high-strength Grade 8 steel, these screws deliver reliable torque retention and superior shear resistance under demanding loads.
- Material: Grade 8 steel — high-tensile strength for heavy loads
- Finish: Plain (uncoated) for versatile post-treatment options
- Thread size: 5/8-18 UNC (coarse thread for quick, secure assemblies)
- Length: 6-1/2 inches
- Drive type: Hex head for standard wrenches or sockets
- Origin: USA-made for consistent quality
Built for reliability in demanding environments, Grade 8 steel provides excellent strength-to-weight ratio and resistance to loosening under vibration when paired with appropriate nuts and washers. The plain finish gives you flexibility for painting, coating, or plating as part of your custom assembly.
Ideal applications:
- Heavy equipment and construction machinery
- Automotive, truck, and fleet maintenance
- Industrial machinery, conveyors, and tooling
Stock up now to ensure you have trusted, domestically manufactured fasteners on hand for your next project.
Can We Help?
If you’re not sure that this product is right for you, give us a call!
800-222-0324