S-91257A682 7/16"-14 x 3 1/4" 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 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
• Optimized installation efficiency with external hex drive design providing secure torque transmission and reduced slippage
• Enhanced thread engagement control through partial threading that allows precise clamping force distribution
• Consistent dimensional accuracy with Class 2A thread fit ensuring reliable mating with standard nuts and components
• Maximum durability from Rockwell C33 hardness that resists wear and deformation under heavy loads
• Industry-standard compatibility with UNC coarse threads that prevent cross-threading and enable quick assembly

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these Grade 8 hex head screws deliver critical performance where failure is not an option. The zinc yellow-chromate plated finish provides superior corrosion resistance for outdoor equipment, machinery, and structural assemblies exposed to moisture and chemicals. The 7/16"-14 UNC coarse thread configuration ensures rapid installation and vibration resistance in heavy machinery, construction equipment, and automotive systems. With partial threading optimizing stress distribution, these heavy-duty fasteners prevent joint loosening while maintaining 150,000 psi tensile strength for critical connections in manufacturing, infrastructure, and transportation sectors where reliability is paramount.

Specification Summary & Compliance

Manufactured to precise Class 2A thread fit tolerances with UNC coarse thread specifications ensuring consistent performance. Complies with ASME B18.2.1 and SAE J429 standards for dimensional accuracy and mechanical properties. Meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental compliance requirements, making these screws suitable for regulated industries and international markets. The 3 1/4" length with 1 1/8" minimum thread length provides optimal engagement for various material thicknesses while maintaining structural integrity.