S-91802A106 4-40 x 1/4" ASME B18.6.3 Stainless Steel Phillips Oval Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction for long-lasting performance in harsh environments
• Exceptional mechanical strength with 80,000 psi tensile strength and Rockwell B80 hardness to withstand high-stress applications
• Precision thread engagement featuring Class 2A thread fit and UNC coarse threading for reliable fastening and reduced cross-threading risk
• Optimized drive efficiency with Phillips No. 1 drive style providing secure torque transfer and reduced cam-out during installation
• Flush surface finish with standard oval head profile and 82° countersink angle for clean, professional appearance in finished assemblies
• Full threading coverage across the entire 1/4" length ensures maximum grip strength and uniform load distribution
• Regulatory compliance assurance meeting ASME B18.6.3 specifications and environmental standards including RoHS 3 and REACH

Professional Applications & Engineering Value

These 4-40 UNC oval head Phillips flat head screws deliver critical performance advantages in demanding industrial environments. The passivated 18-8 stainless steel construction provides exceptional resistance to corrosion and chemical exposure, making them ideal for machinery assembly, electronic enclosures, and outdoor equipment where environmental factors threaten fastener integrity. The combination of coarse UNC threading and Class 2A thread fit ensures rapid installation with minimal cross-threading incidents, while the fully threaded design maximizes holding power across the entire engagement length. The oval head profile with 82° countersink angle creates a smooth, finished appearance that eliminates protrusions in precision assemblies. These flat head screws solve common engineering challenges by providing reliable fastening that maintains integrity under vibration, thermal cycling, and mechanical stress conditions.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit tolerance and UNC coarse thread specifications. These 4-40 oval head screws feature a 0.212" head diameter and 1/4" length with complete threading. Compliance includes ASME B18.6.3 mechanical standards, RoHS 3 (2015/863/EU) environmental directive, and REACH (EC 1907/2006) chemical regulation compliance, ensuring suitability for global industrial applications and regulatory requirements.