S-91251A422 3/8"-24 x 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.
• Superior corrosion resistance from the black-oxide finish extends service life in demanding industrial environments.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies in critical applications.
• Fine UNF threads offer improved load distribution and better sealing capabilities compared to coarse threads.
• Fully threaded design allows for maximum grip and adjustability along the entire length of the screw.
• Hex socket drive enables high torque application and easy installation in confined spaces with standard tools.
• Rockwell C37 hardness maintains structural integrity and wear resistance through repeated use cycles.

Professional Applications & Engineering Value

These black-oxide alloy steel socket head cap screws are engineered to address common industrial challenges where vibration resistance, corrosion protection, and precise fitment are critical. The 3/8"-24 UNF fine thread configuration with Class 3A precision fit ensures minimal backlash in machinery, automotive, and aerospace assemblies where dimensional stability is paramount. The combination of 170,000 psi tensile strength and Rockwell C37 hardness provides exceptional durability against dynamic loads and fatigue, while the black-oxide surface treatment offers superior protection against oxidation and chemical exposure in harsh operating environments. These fully threaded fasteners deliver reliable performance in precision equipment, manufacturing fixtures, and heavy-duty machinery applications where failure is not an option.

Specification Summary & Compliance

This socket head cap screw features precise Class 3A thread fit with 3/8"-24 UNF fine threads and meets ASTM A574 manufacturing specifications. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global industrial markets. Dimensions include 3/4" length, 9/16" head diameter, and 5/16" hex drive size for standardized tool compatibility.