Description
5/16"-18 Grade 8 Indented Hex Flange Screws (Frame Bolts)
Heavy-Duty Grade 8 Alloy Steel with Black Phosphate & Oil Finish
Upgrade your fastening solution with our premium 5/16"-18 Grade 8 Indented Hex Flange Screws, also known as Frame Bolts or Hex Flange Screws. Built from high-strength Grade 8 alloy steel, these bolts feature a built-in flange head for even load distribution and a durable black phosphate & oil finish for mild corrosion resistance and improved torque performance. Perfect for automotive, construction, and heavy machinery applications.
Key Features
- Diameter: 5/16 inch
- Thread Size: 5/16"-18 (18 TPI) – Coarse Thread
- Thread Length: Available in Full or Partial Thread (FT = Full Thread)
- Wrench Size (Across Flats): 1/2 inch
- Head Style: Indented Hex Flange Head
- Finish: Black Phosphate & Oil for mild corrosion resistance and installation lubrication
- System of Measurement: Inch (Imperial / US)
- Material: Grade 8 Alloy Steel
- Specifications: SAE J429 / ASME B18.2.1 compliant
Material & Finish Advantages
- Grade 8 Strength: Ideal for high-load applications in structural, mechanical, and automotive environments.
- Integrated Flange: Washer-style head helps spread load and reduce the need for separate washers.
- Lubricated Finish: Black phosphate & oil aids in smooth torqueing and resists light corrosion.
Common Applications
- Vehicle Frame & Suspension Systems
- Construction Equipment
- Industrial Machinery
- Metal Fabrication & Brackets
Why Choose Monster Bolts Flange Screws?
- Built to Perform: Dependable Grade 8 fasteners for mission-critical applications.
- Integrated Design: Built-in flange for added strength and convenience.
- Bulk Option Available: Order in high-quantity packaging for industrial needs. Buy Bulk Here
- Precision Manufactured: Meets or exceeds key fastener standards.
Installation Tips
- Use with a torque wrench to ensure proper preload under stress.
- Always check for proper flange contact with mating surface.
- Match with appropriate Grade 8 nuts if required (sold separately).
Note: (FT) = Full Thread. Always confirm thread length requirements for your project.
Order Yours Today
Power your project with 5/16"-18 Grade 8 Indented Hex Flange Screws from Monster Bolts. Engineered for strength, consistency, and reliability. Order now and enjoy fast U.S. shipping and expert-level customer support.
✔️ Grade 8 Alloy Steel – Built for strength
✔️ Black Phosphate & Oil Finish – Resists light corrosion and eases installation
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