S-91772A121 4-40 x 2" ASME B18.6.3 Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh industrial environments
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B70 hardness for reliable performance in demanding applications
• Secure and efficient installation through Phillips No. 1 drive design, preventing cam-out during torque application
• Precision threading with Class 2A UNC coarse threads ensuring consistent engagement and vibration resistance
• Full threading along 2" length provides maximum grip and load distribution across the entire fastener
• Standard pan head profile offers excellent bearing surface and clean aesthetic appearance
• Comprehensive compliance with ASME B18.6.3 standards and environmental regulations including RoHS 3 and REACH

Professional Applications & Engineering Value

These 4-40 UNC fully threaded machine screws deliver critical performance advantages in industrial fastening applications where corrosion resistance and mechanical reliability are paramount. The passivated 18-8 stainless steel construction provides exceptional protection against oxidation and chemical exposure, making them ideal for manufacturing equipment, electronic enclosures, and outdoor installations. The coarse thread spacing and Class 2A thread fit ensure rapid assembly and secure fastening in various materials, while the pan head design with Phillips drive facilitates efficient installation without specialized tools. Engineered to maintain integrity under sustained loads, these rounded head screws solve common challenges of fastener failure in vibration-prone environments and corrosive conditions.

Specification Summary & Compliance

This high-performance fastener maintains Class 2A thread fit tolerance per UNC standards with precise 4-40 thread size and coarse thread spacing. Manufacturing and dimensional specifications strictly conform to ASME B18.6.3 requirements. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global industrial markets. The 2" length and fully threaded design provide consistent performance meeting industrial fastener specifications.