S-91099A465 5-40 x 3/8" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh industrial environments
• Excellent load-bearing capability with 80,000 psi tensile strength and Rockwell B80 hardness for reliable performance
• Secure and flush installation thanks to the 82° countersink angle and undercut flat head profile
• Optimized driving efficiency with Phillips No. 1 drive style, reducing cam-out and tool slippage
• Consistent threading performance with Class 2A thread fit and coarse UNC threads for quick assembly
• Full regulatory compliance meeting ASME B18.6.3, RoHS 3, and REACH standards for global applications
• Complete thread coverage with fully threaded 3/8" length for maximum grip and holding power

Professional Applications & Engineering Value

These 5-40 UNC flat head screws deliver exceptional engineering value in demanding applications where material integrity and precision matter. The passivated 18-8 stainless steel construction provides superior resistance to corrosion and chemical exposure, making them ideal for industrial equipment, electronic enclosures, and machinery subjected to harsh operating conditions. The combination of Class 2A thread fit and coarse UNC threading ensures reliable engagement and vibration resistance, while the undercut flat head profile with 82° countersink angle allows for flush mounting in precision assemblies. With 80,000 psi tensile strength and full compliance with major industry standards, these screws solve critical fastening challenges in manufacturing, aerospace, and automotive sectors where failure is not an option.

Specification Summary & Compliance

This 5-40 UNC flat head screw maintains precise Class 2A thread fit tolerances according to ASME B18.6.3 specifications, ensuring consistent threading performance. The coarse thread spacing and right-hand thread direction provide optimal engagement characteristics for industrial applications. Manufacturing compliance includes full adherence to ASME B18.6.3 mechanical standards, RoHS 3 (2015/863/EU) environmental directives, and REACH (EC 1907/2006) chemical regulations, guaranteeing safety and reliability in global markets.