S-90471A429 4-40 x 1" ASME B18.6.3 Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for extended service life in demanding environments
• High-strength performance with 60,000 psi tensile strength and Rockwell B70 hardness for reliable, vibration-resistant fastening
• Precision thread fit with Class 2A UNC coarse threads ensuring smooth installation and consistent engagement
• Efficient installation with Phillips No. 1 drive and standard flat head profile for flush mounting and secure tool engagement
• Full-threaded design providing maximum grip length and uniform load distribution across the entire fastener
• Regulatory compliance meeting ASME B18.6.3 standards and environmental regulations including RoHS 3 and REACH
• Versatile 1" length offering optimal fastening depth for various material thicknesses in industrial assemblies

Professional Applications & Engineering Value

These 4-40 UNC flat head Phillips screws deliver critical engineering solutions where flush surface mounting and high tensile strength are paramount. The zinc-plated steel construction provides essential corrosion protection for industrial equipment, electronic enclosures, and machinery subjected to environmental exposure. The coarse UNC threads and Class 2A thread fit ensure rapid installation with reduced cross-threading risks, while the fully threaded design maintains consistent clamping force across joint interfaces. The standard flat head profile with 100° countersink angle enables seamless integration into precision assemblies where protruding fasteners are unacceptable, making these screws ideal for automotive components, electrical panels, and manufacturing fixtures requiring reliable, vibration-resistant fastening solutions.

Specification Summary & Compliance

These flat head screws feature precise Class 2A thread fit with UNC coarse thread spacing (4-40 thread size) and maintain dimensional accuracy per ASME B18.6.3 specifications. The manufacturing process ensures compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, while delivering consistent mechanical properties including 60,000 psi tensile strength and Rockwell B70 hardness for reliable performance in industrial fastening applications.