S-91247A919 1"-8 x 3 3/4" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 120,000 psi tensile strength for reliable performance in demanding industrial applications
• Superior corrosion resistance through zinc plating, extending service life in harsh environments
• Optimized thread engagement with 1"-8 UNC coarse threading for faster assembly and reduced cross-threading risk
• Precision torque transmission via external hex drive and hex head design for secure tightening with standard tools
• Controlled partial threading providing unthreaded shank section for enhanced shear strength where needed
• Consistent mechanical properties with Rockwell C25 hardness ensuring dimensional stability under stress
• Regulatory compliance assurance meeting major industrial and environmental standards for global supply chain compatibility

Professional Applications & Engineering Value

This Grade 5 hex head screw delivers critical engineering solutions for heavy machinery, structural steel connections, and industrial equipment assembly. The zinc plated steel construction provides essential corrosion protection in manufacturing facilities and outdoor applications, while the 1"-8 UNC coarse thread design enables rapid installation in thick materials and castings. The partially threaded configuration offers distinct advantages in pivot points and shear applications where unthreaded shank sections prevent loosening under vibrational loads. With 120,000 psi tensile strength and controlled hardness, this fastener maintains clamp load integrity in high-stress environments, making it ideal for construction equipment, agricultural machinery, and transportation infrastructure where reliability is paramount.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit tolerance for consistent assembly performance. This hex head screw complies with ASME B18.2.1 and SAE J429 specifications for mechanical properties and dimensional requirements. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting current environmental regulations for hazardous substance restrictions. The 3 3/4" length with 2 1/4" minimum thread length provides versatile fastening capabilities across various material thicknesses.