S-91251A420 3/8"-24 x 3/8" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance in high-stress applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide finish extends service life in harsh industrial environments, minimizing maintenance needs.
• Precision Class 3A thread fit provides tight tolerances and secure fastening, ideal for applications requiring vibration resistance and leak prevention.
• High hardness rating (Rockwell C37) offers excellent wear resistance, maintaining thread integrity through repeated use.
• 5/16" hex drive design allows for easy installation and high torque application with standard tools, improving assembly efficiency.
• Fully threaded construction ensures consistent engagement along the entire length, providing uniform clamping force.
• Compliance with ASTM A574, RoHS 3, and REACH guarantees material quality and environmental safety for global supply chain integration.

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw is engineered to address critical challenges in demanding industrial settings. The 3/8"-24 UNF fine thread configuration delivers superior vibration resistance and precise alignment in machinery, automotive, and aerospace assemblies where Class 3A thread fit is essential for safety and performance. The alloy steel construction combined with 170,000 psi tensile strength prevents stripping and shear failure under extreme loads, while the black-oxide surface treatment provides reliable corrosion protection without compromising dimensional accuracy. These features make it an optimal choice for high-strength socket screw applications requiring durability, regulatory compliance, and consistent performance in critical fastening systems.

Specification Summary & Compliance

This socket head cap screw features 3/8"-24 UNF fine threads with Class 3A thread fit for precise dimensional accuracy. It meets ASTM A574 manufacturing specifications for high-strength alloy steel fasteners and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring suitability for international industrial applications.