S-91251A041 3/4"-16 x 1 1/4" 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 on alloy steel, extending service life in demanding industrial environments.
• Precise thread engagement with UNRF fine threads and Class 3A fit, providing secure, vibration-resistant connections.
• High hardness rating of Rockwell C37 offers excellent wear resistance, maintaining thread integrity over repeated use.
• Easy installation and removal with a 5/8" hex drive socket head, allowing for high torque application in confined spaces.
• Full threading along the 1 1/4" length ensures uniform load distribution and versatile mounting options.
• Compliance with industry standards including ASTM A574, RoHS 3, and REACH, guaranteeing safety and environmental responsibility.

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw is engineered to address critical challenges in heavy-duty industrial settings, such as machinery assembly, automotive systems, and construction equipment. The UNRF fine thread design with Class 3A fit minimizes loosening under vibration, while the high tensile strength and Rockwell C37 hardness prevent stripping and deformation under extreme loads. The corrosion-resistant black-oxide surface enhances durability in humid or chemically aggressive environments, reducing maintenance needs. Ideal for applications requiring precision fastening and long-term reliability, this screw ensures consistent performance in high-strength industrial fastening scenarios.

Specification Summary & Compliance

This socket head cap screw features a 3/4"-16 UNRF fine thread with Class 3A thread fit for precise tolerance, ensuring secure connections. It meets ASTM A574 specifications for high-strength alloy steel fasteners and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its safety and environmental standards. The fully threaded design and consistent dimensions support reliable performance in industrial applications.