S-90585A132 6-40 x 3/8" ASME B18.3, ASTM F879 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh chemical and marine environments.
• Precise, secure fastening thanks to Class 3A thread fit and 6-40 UNF fine threading, minimizing the risk of loosening under vibration.
• High mechanical strength with 70,000 psi tensile strength and Rockwell B55 hardness, ensuring durability in demanding applications.
• Flush, professional installation enabled by the standard flat head profile and 82° countersink angle for a smooth surface finish.
• Easy, reliable driving with a 5/64" hex drive, providing excellent torque transfer and reducing tool slippage.
• Full regulatory compliance meeting ASME B18.3, RoHS 3, and REACH standards, ensuring safety and environmental responsibility.
• Versatile industrial use with fully threaded 3/8" length, offering consistent holding power across various material thicknesses.

Professional Applications & Engineering Value

This 316 stainless steel flat head screw is engineered to address critical challenges in industrial and marine settings where corrosion resistance and mechanical reliability are paramount. The passivated finish enhances the innate corrosion resistance of 316 stainless steel, making it suitable for exposure to chlorides, acids, and extreme weather conditions. Its 6-40 UNF fine thread and Class 3A fit provide superior vibration resistance and precise engagement in tapped holes, reducing the risk of thread stripping in softer materials or high-cycle applications. The flat head design with an 82° countersink ensures a flush mount, essential for aerodynamic surfaces, machinery guards, and assembly lines where protrusions are unacceptable. Combined with a hex drive for secure installation, this screw delivers long-term performance in chemical processing equipment, offshore platforms, and food-grade machinery.

Specification Summary & Compliance

This screw adheres to Class 3A thread fit for high precision and UNF fine thread standards. Manufacturing and dimensional specifications conform to ASME B18.3. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free of hazardous substances and safe for various industrial applications.