S-91249A310 4-40 x 1 1/4" ASME B18.6.3 Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with Black-Oxide coated 18-8 Stainless Steel construction, ideal for harsh industrial environments
• Superior holding power from 70,000 psi tensile strength and full threading for maximum load distribution
• Reliable fastening performance with Class 2A thread fit ensuring consistent engagement and vibration resistance
• Quick installation and removal using standard Phillips #1 drive, compatible with common industrial tools
• Optimized head design with rounded pan profile providing a finished appearance and reduced surface protrusion
• Wide compatibility with UNC coarse 4-40 threading for versatile use across various assembly applications
• Regulatory compliance assurance meeting ASME B18.6.3 standards and environmental regulations for global sourcing

Professional Applications & Engineering Value

These 4-40 UNC rounded pan head screws deliver critical engineering solutions where corrosion resistance and mechanical reliability are paramount. The Black-Oxide 18-8 Stainless Steel construction provides enhanced protection against oxidation and chemical exposure, making them ideal for electronic enclosures, machinery panels, and automotive components operating in demanding conditions. The combination of coarse threading and Class 2A thread fit ensures rapid assembly with minimal cross-threading risk, while the fully threaded design maximizes grip length for superior vibration resistance in dynamic applications. The Phillips drive system offers familiar, tool-compatible installation that maintains efficiency in high-volume production environments.

Specification Summary & Compliance

Manufactured to precise Class 2A thread tolerances with UNC 4-40 coarse threading and compliant with ASME B18.6.3 mechanical standards. These screws maintain dimensional accuracy with 1-1/4" length and 0.219" head diameter specifications. Environmental compliance is verified through RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring safe use in international markets. The manufacturing process adheres to strict quality controls for consistent performance in industrial fastener applications.