S-90128A575 1/4"-20 x 5 1/2" 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.
• Zinc-plated alloy steel construction provides excellent corrosion resistance, extending service life in demanding industrial environments.
• Class 3A thread fit offers tighter tolerances for superior fastening precision and vibration resistance in critical assemblies.
• UNC coarse threading enables quicker installation and reduced cross-threading risk, improving assembly efficiency.
• Partially threaded design allows for precise clamping force control and secure positioning in varied material thicknesses.
• Hex socket drive with 3/16" drive size facilitates high-torque application and access in confined spaces.
• Compliance with ASTM A574, RoHS 3, and REACH ensures material consistency, environmental safety, and regulatory acceptance for global supply chains.

Professional Applications & Engineering Value

This zinc-plated alloy steel socket head cap screw is engineered to address common industrial fastening challenges, such as joint integrity under dynamic loads and corrosion in harsh environments. The 1/4"-20 UNC coarse thread with Class 3A fit provides secure, repeatable fastening in machinery, automotive, and construction applications, minimizing loosening from vibrations. Its high tensile strength and Rockwell C37 hardness ensure durability in heavy-duty assemblies, while the hex drive allows for efficient installation with standard tools. Ideal for use in industrial fasteners requiring precise torque and long-term reliability, this screw delivers consistent performance where material strength and compliance with standards like ASTM A574 are critical.

Specification Summary & Compliance

This socket head cap screw features a 1/4"-20 UNC coarse thread with Class 3A thread fit for high precision, a length of 5 1/2", and a partially threaded rod type. It meets ASTM A574 specifications for material and manufacturing, and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and suitability for industrial use.