S-91770A851 4-40 x 7/16" ASME B18.6.3 Stainless Steel Truss Head Phillips Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh industrial environments
• Superior holding power from 70,000 psi tensile strength and Rockwell B70 hardness, ensuring reliable fastening under stress
• Enhanced load distribution thanks to the wide rounded truss head design, reducing surface damage and material stress
• Quick and secure installation with No. 1 Phillips drive and coarse UNC threading, minimizing assembly time
• Precise thread engagement through Class 2A fit and fully threaded design, providing consistent performance in repetitive applications
• Broad regulatory compliance with ASME B18.6.3, RoHS 3, and REACH standards, ensuring safety and environmental responsibility
• Versatile 7/16" length with right-hand threading, suitable for various material thicknesses in industrial assemblies

Professional Applications & Engineering Value

These 4-40 UNC Rounded Truss Head Phillips Screws deliver critical engineering solutions where vibration resistance, corrosion protection, and consistent torque application are paramount. The passivated 18-8 stainless steel material prevents oxidation and chemical degradation, making these fasteners ideal for electronics enclosures, machinery panels, and outdoor equipment. The combination of coarse thread spacing and Class 2A thread fit ensures rapid installation with reduced cross-threading risks in high-volume production lines. The wide truss head profile distributes clamping force effectively, preventing damage to softer materials while maintaining secure fastening under dynamic loads. These characteristics make them particularly valuable in automotive, aerospace, and industrial manufacturing applications where reliability and compliance with ASME B18.6.3 standards are non-negotiable.

Specification Summary & Compliance

This fastener maintains Class 2A thread fit per UNC standards with coarse thread spacing and full threading along the 7/16" length. Manufacturing conforms to ASME B18.6.3 specifications for dimensional accuracy and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring adherence to environmental and safety standards for industrial components.