S-91251A601 1 1/4"-12 x 3" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance under high-stress conditions, reducing the risk of fastener failure.
• Black-oxide coating on alloy steel provides corrosion resistance and a durable finish, extending service life in harsh industrial environments.
• Fully threaded UNRF fine thread design with Class 2A fit offers precise engagement and vibration resistance for secure, long-lasting assemblies.
• 7/8" hex drive and standard socket head allows for high-torque installation with common tools, improving assembly efficiency and reducing stripping risk.
• Compliance with ASTM A574 guarantees consistent quality and mechanical properties, ensuring interchangeability and reliability in critical applications.
• RoHS 3 and REACH compliant construction meets environmental regulations, making it suitable for global supply chains and eco-conscious projects.
• Rockwell C37 hardness provides excellent wear resistance, maintaining thread integrity through repeated use and adjustments.

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw is engineered to address common industrial challenges such as vibration loosening and corrosion in heavy machinery, automotive, and construction equipment. The UNRF fine thread and Class 2A fit ensure tight, precise connections that resist back-off under dynamic loads, while the fully threaded design allows for uniform clamping force across the entire 3" length. Its high tensile strength and Rockwell C37 hardness make it ideal for high-stress applications where durability and reliability are critical, reducing maintenance downtime and enhancing operational safety in demanding environments.

Specification Summary & Compliance

This socket head cap screw features a 1 1/4"-12 UNRF fine thread with Class 2A dimensional tolerance for precise fit and interchangeability. Manufactured in accordance with ASTM A574 specifications, it ensures consistent mechanical properties and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting environmentally responsible sourcing and use in industrial applications.