S-91251A441 1/4"-28 x 7/8" 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 industrial applications, reducing the risk of fastener failure.
• Class 3A fine thread fit provides superior precision and vibration resistance, maintaining secure connections in demanding environments.
• Black-oxide coating on alloy steel enhances corrosion resistance and durability, extending service life in harsh conditions.
• Rockwell C37 hardness offers excellent wear resistance, minimizing deformation under heavy loads and repeated use.
• Fully threaded design allows for consistent clamping force along the entire length, improving assembly stability.
• Compliance with RoHS 3 and REACH regulations ensures environmental safety and meets global standards for hazardous substance restrictions.
• ASTM A574 certification guarantees material quality and manufacturing consistency, providing peace of mind for critical applications.

Professional Applications & Engineering Value

These socket head cap screws are engineered with black-oxide alloy steel and UNRF fine threads to address common industrial challenges such as vibration loosening and corrosion. The Class 3A thread fit ensures tight tolerances, making them ideal for precision machinery, automotive assemblies, and heavy-duty equipment where reliable fastening is critical. By combining high tensile strength and fine thread specifications, they reduce maintenance needs and enhance operational safety in environments exposed to dynamic loads and harsh conditions, delivering long-term engineering value.

Specification Summary & Compliance

This product features a 1/4"-28 UNRF fine thread with Class 3A fit for precise engagement, manufactured to ASTM A574 standards. It complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring adherence to environmental and safety requirements without hazardous substances.