S-91253A357 3/8"-24 x 1 1/4" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 130,000 PSI ensures reliable performance in high-stress applications, reducing the risk of fastener failure.
• Precision Class 3A thread fit provides superior engagement and vibration resistance, minimizing loosening in dynamic environments.
• Black-oxide finish on alloy steel offers enhanced corrosion resistance and a durable, non-reflective surface for long-term use.
• Fully threaded design allows for maximum grip and adjustability along the entire length, simplifying installation.
• 82° countersink angle and flat head enables a flush finish, improving aesthetics and safety in assembled products.
• Hex drive (7/32") facilitates easy installation and removal with standard tools, reducing assembly time.
• High hardness (Rockwell C39) ensures wear resistance and maintains thread integrity through repeated use.

Professional Applications & Engineering Value

This 3/8"-24 UNF flat head socket cap screw is engineered to address critical needs in industrial and mechanical assemblies where space constraints and high strength are paramount. The black-oxide alloy steel construction provides excellent durability and resistance to environmental factors, while the fine UNF threads and Class 3A fit ensure secure fastening in vibrating machinery, automotive components, and precision equipment. Its fully threaded body and 82° countersink allow for seamless integration into tapered holes, reducing protrusion and enhancing structural integrity. Ideal for applications requiring reliable, high-strength fasteners that comply with rigorous industry standards, this screw minimizes maintenance and downtime in demanding environments.

Specification Summary & Compliance

This screw adheres to precise dimensional standards, including Class 3A thread fit and UNF fine threading for accurate engagement. It meets ASME B18.3 and ASTM F835 specifications, ensuring consistent quality and performance. Additionally, it is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting environmentally responsible and safe use in global markets.