S-91257A679 7/16"-14 x 2 1/2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Maximum load-bearing capacity with Grade 8 classification and 150,000 psi tensile strength for critical heavy-duty applications
• Superior corrosion resistance through zinc yellow-chromate plating that protects against harsh industrial environments
• Optimized thread engagement with UNC coarse threading and Class 2A fit ensuring reliable installation and vibration resistance
• Enhanced driving efficiency with external hex head design providing secure tool engagement and high torque capability
• Controlled thread distribution through partial threading that concentrates strength where needed most
• Industry-standard compliance meeting ASME B18.2.1 and SAE J429 specifications for guaranteed performance
• Environmental responsibility with RoHS 3 and REACH compliance for sustainable manufacturing practices

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these Grade 8 hex head screws deliver exceptional performance in construction machinery, heavy equipment assembly, and structural frameworks. The 7/16"-14 UNC coarse thread configuration provides superior resistance to vibration loosening while enabling faster installation in thick materials. The zinc yellow-chromate plating creates a protective barrier against corrosion in outdoor or high-moisture environments, significantly extending service life. With partial threading concentrating the fastener's strength in the engaged section, these screws prevent thread stripping and maintain clamping force under extreme loads. The external hex drive design ensures compatibility with standard tools while allowing high torque application without cam-out, making them ideal for maintenance and assembly operations where reliability is paramount.

Specification Summary & Compliance

This 2 1/2" length hex head screw features precise Class 2A thread fit with UNC coarse threading (7/16"-14) ensuring proper engagement and dimensional accuracy. Manufactured to ASME B18.2.1 and SAE J429 standards, the fastener maintains consistent quality and performance characteristics. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, containing no restricted substances while meeting the latest compliance requirements for industrial applications.