S-91251A553 1/4"-20 x 2 3/4" 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 in demanding applications.
• Black-oxide coating on alloy steel provides enhanced corrosion resistance and a durable finish, extending service life in harsh industrial environments.
• Precision Class 3A thread fit with 1/4"-20 UNRC coarse threads offers superior engagement and vibration resistance, minimizing loosening in machinery and equipment.
• Hex socket drive design allows for high-torque installation and easy access in confined spaces, improving assembly efficiency and reducing tool slippage.
• Rockwell C37 hardness rating delivers excellent wear resistance and durability, maintaining structural integrity over repeated use cycles.
• Compliance with ASTM A574, RoHS 3, and REACH ensures adherence to rigorous quality and environmental standards, providing peace of mind for regulated industries.
• Partially threaded shank enables secure clamping where full threading isn't required, offering versatility for various mounting and fastening needs.

Professional Applications & Engineering Value

These socket head cap screws are engineered to address critical challenges in industrial fastening, where high tensile loads and vibration resistance are paramount. The black-oxide alloy steel construction combats corrosion and wear, making them ideal for machinery, automotive assemblies, and heavy equipment exposed to demanding conditions. With a 1/4"-20 coarse thread and Class 3A fit, they provide precise, reliable engagement that reduces the risk of stripping or loosening under dynamic loads. The hex drive design facilitates efficient installation in tight spaces, enhancing productivity while the partially threaded configuration allows for optimal clamp load distribution. By meeting ASTM A574 specifications, these screws deliver consistent performance for engineers and procurement specialists seeking durable, compliant industrial fasteners.

Specification Summary & Compliance

This product features precise inch system dimensions including a 2 3/4" length and 3/16" hex drive, with threads manufactured to UNRC coarse thread standards and a Class 3A thread fit for superior tolerance control. It complies with ASTM A574 manufacturing specifications for socket head cap screws, ensuring consistent quality and performance. Environmental and safety compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) requirements, making these screws suitable for regulated industrial applications worldwide.