S-91286A520 3/4"-16 x 5" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with Grade 8 steel construction and 150,000 psi tensile strength for reliable performance in demanding applications
• Superior corrosion resistance provided by zinc-flake coating, ensuring long-term durability in harsh industrial environments
• Precise thread engagement with Class 2A thread fit and UNF fine threading for secure fastening and vibration resistance
• Optimized torque transmission through the external hex drive and 1 1/8" head width for easy installation with standard tools
• Enhanced fatigue resistance from Rockwell C33 hardness, maintaining structural integrity under repeated stress cycles
• Versatile partial threading design allowing both threaded and unthreaded sections for flexible application in various assembly configurations
• Regulatory compliance assurance meeting ASME B18.2.1, SAE J429, RoHS 3, and REACH standards for quality and environmental safety

Professional Applications & Engineering Value

This Grade 8 hex head screw delivers critical engineering solutions for heavy-duty industrial applications where failure is not an option. The combination of 150,000 psi tensile strength steel and Rockwell C33 hardness provides exceptional resistance to structural fatigue and permanent deformation under extreme loads. The 3/4"-16 UNF fine threading with Class 2A thread fit ensures precise engagement in tapped holes, reducing the risk of cross-threading while maintaining vibration resistance in machinery, construction equipment, and automotive assemblies. The zinc-flake coating offers superior corrosion protection compared to conventional platings, making these partially threaded hex screws ideal for outdoor equipment, marine applications, and chemical processing environments where moisture and corrosive elements are present.

Specification Summary & Compliance

This 5" length hex head screw features precise Class 2A thread fit with 3/4"-16 UNF fine threading and 1 3/4" minimum thread length. Manufactured to ASME B18.2.1 specifications and SAE J429 Grade 8 requirements, ensuring dimensional accuracy and mechanical performance. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, containing no restricted substances above threshold limits.