S-91099A459 4-40 x 7/16" 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
• Exceptional tensile strength rated at 80,000 psi for reliable, long-lasting fastening performance
• Precision thread engagement with Class 2A fit and UNC coarse threads ensuring secure installation
• Optimized flush mounting featuring 82° countersink angle and undercut flat head design
• Enhanced drive stability with No. 1 Phillips drive preventing cam-out during installation
• Consistent mechanical properties maintained through Rockwell B80 hardness rating
• Full regulatory compliance meeting ASME B18.6.3, RoHS 3, and REACH standards

Professional Applications & Engineering Value

These 4-40 UNC flat head screws deliver critical engineering solutions where corrosion resistance and precision matter most. The passivated 18-8 stainless steel construction provides exceptional protection against oxidation and chemical exposure, making them ideal for marine, food processing, and outdoor equipment applications. The undercut flat head profile ensures perfect flush mounting in countersunk holes, eliminating protrusion issues in precision assemblies. With fully threaded coarse UNC threads and Class 2A fit, these Phillips drive screws offer superior engagement in both metallic and composite materials, reducing installation time while maintaining vibration resistance in demanding industrial environments.

Specification Summary & Compliance

Manufactured to exacting ASME B18.6.3 specifications with Class 2A thread fit tolerance for consistent performance. Features 4-40 UNC coarse threads with right-hand threading and 7/16" length. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global markets.