S-90471A157 4-40 x 5/16" ASME B18.6.3 Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with zinc-plated steel construction for long-lasting performance in demanding environments
• Superior holding power with 60,000 psi tensile strength and Rockwell B70 hardness for reliable, vibration-resistant fastening
• Optimized installation efficiency through Phillips No. 1 drive design and fully threaded coarse UNC pattern
• Precise flush mounting with standard 100° countersink angle and flat head profile for seamless surface integration
• Consistent thread engagement with Class 2A thread fit ensuring smooth assembly and reduced cross-threading risks
• Regulatory compliance assurance meeting ASME B18.6.3 specifications and environmental standards including RoHS 3 and REACH
• Versatile 5/16" length providing optimal fastening depth for various material thicknesses in industrial assemblies

Professional Applications & Engineering Value

These zinc-plated steel flat head screws deliver critical performance advantages for industrial fastening applications where reliability and corrosion resistance are paramount. The combination of 60,000 psi tensile strength and Rockwell B70 hardness ensures exceptional durability against vibration loosening and mechanical stress, while the zinc plating provides essential protection against environmental degradation. The 4-40 UNC coarse thread configuration offers superior pull-out resistance in various materials, and the 100° countersink angle enables perfect flush mounting for applications requiring smooth surface profiles. Engineered to ASME B18.6.3 standards, these Phillips drive screws are ideal for electronics enclosures, machinery components, and assembly lines where consistent performance and regulatory compliance are mandatory requirements.

Specification Summary & Compliance

This flat head Phillips screw maintains precise Class 2A thread fit tolerances with 4-40 UNC coarse threading and right-hand thread direction. Manufacturing and quality control strictly adhere to ASME B18.6.3 specifications, ensuring dimensional accuracy and performance reliability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming its suitability for global industrial applications with stringent material restrictions.