S-91571A401 1/2"-13 x 2 1/4" ASME B18.2.6, ASTM A325, ASTM F3125 Medium-Strength Steel Heavy Hex Head Screws for Structural Applications

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 120,000 psi tensile strength for reliable performance in heavy structural applications
• Superior hardness and durability with Rockwell C19 rating to resist wear and deformation under extreme conditions
• Optimized thread engagement through partially threaded design and Class 2A thread fit for secure fastening and vibration resistance
• Easy installation and removal with standard 7/8" external hex head design compatible with common tools
• Industry-standard compliance meeting ASME B18.2.6, ASTM A325, and ASTM F3125 specifications for quality assurance
• Environmental responsibility with RoHS 3 and REACH compliance for sustainable procurement
• Versatile coarse threading with 1/2"-13 UNC pattern for quick assembly in various materials

Professional Applications & Engineering Value

This Grade A325 hex head structural screw delivers critical engineering solutions for demanding industrial environments. The high-strength steel construction combined with Rockwell C19 hardness ensures reliable performance in structural steel connections, heavy machinery assembly, and construction applications where vibration resistance and load capacity are paramount. The partially threaded design provides optimal clamp load distribution while the coarse UNC threading enables faster installation in structural steel and other heavy materials. Engineered to meet rigorous ASTM A325 specifications, this fastener maintains structural integrity in critical joints, bridge construction, and industrial framework applications where failure is not an option. The external hex drive facilitates efficient installation with standard tools, reducing labor time while maintaining precise torque requirements.

Specification Summary & Compliance

This heavy-duty fastener features Class 2A thread fit tolerance for precise engagement and reliable performance. Manufactured in accordance with ASME B18.2.6, ASTM A325, and ASTM F3125 specifications, ensuring dimensional accuracy and mechanical properties. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting current environmental regulations for hazardous substances. With 1/2"-13 UNC coarse threading and right-hand thread direction, this screw delivers standardized performance across industrial applications requiring Grade A325 structural fasteners.