S-91251A477 3/8"-24 x 6" 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.
• Precision Class 3A thread fit provides superior engagement and vibration resistance, minimizing loosening in critical assemblies.
• Black-oxide coating on alloy steel offers enhanced corrosion resistance and a durable, non-reflective finish suitable for industrial environments.
• Partially threaded design allows for secure clamping while leaving an unthreaded shank for precise alignment and shear strength.
• 5/16" hex drive socket head enables high-torque installation with standard tools, ensuring easy assembly and disassembly in confined spaces.
• Fine UNF thread (3/8"-24) delivers improved load distribution and finer adjustment capability compared to coarse threads.
• Full compliance with ASTM A574 guarantees material quality and manufacturing consistency for engineering-critical applications.

Professional Applications & Engineering Value

These black-oxide alloy steel socket head cap screws are engineered to address common industrial challenges such as vibration-induced loosening, corrosion in harsh environments, and the need for high clamping force. The Class 3A UNF fine threads provide exceptional thread engagement and resistance to dynamic loads, making them ideal for precision machinery, automotive assemblies, and heavy equipment where reliability and dimensional accuracy are paramount. The combination of 170,000 psi tensile strength and Rockwell C37 hardness ensures these fasteners maintain integrity under extreme mechanical stress, while the black-oxide surface treatment extends service life by protecting against oxidation without adding significant thickness that could affect fit.

Specification Summary & Compliance

This socket head cap screw features 3/8"-24 UNF fine threads with Class 3A thread fit for precision tolerance, a 6" length with partial threading, and meets ASTM A574 material specifications. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring suitability for global industrial markets requiring verified material safety and performance standards.