S-91772A106 4-40 x 1/4" ASME B18.6.3 Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance from passivated 18-8 stainless steel construction, ensuring long-term reliability in harsh environments
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B70 hardness for reliable load-bearing performance
• Precision thread engagement with Class 2A fit and UNC coarse threads providing secure fastening and vibration resistance
• Optimized drive efficiency through Phillips No. 1 drive design enabling quick installation and reduced assembly time
• Enhanced durability with fully threaded design ensuring maximum grip length and uniform stress distribution
• Industry-standard compliance meeting ASME B18.6.3 specifications for consistent quality and interchangeability
• Environmental responsibility with RoHS 3 and REACH compliance for safe use in regulated applications

Professional Applications & Engineering Value

These 4-40 UNC rounded pan head screws deliver critical performance advantages for industrial assembly 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 these fully threaded fasteners ideal for electronics enclosures, machinery components, and outdoor equipment. The combination of Class 2A thread fit with coarse UNC threading ensures rapid installation and secure fastening in various materials, while the rounded pan head profile with Phillips No. 1 drive offers flush mounting and efficient torque transfer. These screws effectively address common engineering challenges including vibration loosening, material degradation, and assembly efficiency in demanding industrial environments.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit and UNC coarse threads (4-40 size), these screws maintain consistent 1/4" length and 0.112" thread diameter for reliable interchangeability. The manufacturing process adheres to ASME B18.6.3 specifications, ensuring dimensional accuracy and performance consistency. Environmental compliance includes full conformance with RoHS 3 (2015/863/EU) requirements and REACH (EC 1907/2006) regulations, confirming these fasteners are free from restricted substances and suitable for global industrial applications.