S-90002A108 5/16"-18 x 3/4" ASME B18.2.1, SAE J429 High-Strength Steel Hex Head Screws with Material Certification

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 PSI tensile strength for reliable performance in high-stress applications
• Superior corrosion protection through zinc yellow-chromate plating that extends service life in harsh environments
• Precise thread engagement with Class 2A fit UNC coarse threads ensuring consistent fastening and vibration resistance
• Maximum drive torque capability thanks to the external hex head design that prevents stripping during installation
• Enhanced material durability from Rockwell C33 hardness that maintains structural integrity under repeated stress
• Full-length threading provides complete engagement along the entire 3/4" length for superior holding power
• Industry-standard compliance meeting ASME B18.2.1 and SAE J429 specifications for guaranteed quality and interchangeability

Professional Applications & Engineering Value

This Grade 8 hex head screw delivers critical engineering solutions for industrial applications where failure is not an option. The combination of 150,000 PSI tensile strength and Rockwell C33 hardness ensures reliable performance in heavy machinery, structural assemblies, and equipment subjected to dynamic loads and vibration. The zinc yellow-chromate plating provides superior corrosion resistance, making these 5/16"-18 UNC coarse thread fasteners ideal for outdoor equipment, automotive components, and manufacturing environments exposed to moisture and chemicals. The fully threaded design and Class 2A thread fit guarantee consistent clamping force distribution, preventing joint loosening in critical applications while the external hex drive allows for high-torque installation without slippage.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit tolerance for consistent performance. The 5/16"-18 UNC coarse thread follows standardized threading specifications while the 3/4" length provides optimal engagement depth. Compliant with ASME B18.2.1 and SAE J429 standards, ensuring material quality, mechanical properties, and dimensional accuracy. The Grade 8 classification guarantees minimum tensile strength of 150,000 PSI and proper hardness characteristics for high-strength applications in industrial and construction settings.