S-90279A103 4-40 x 3/4" ASME B18.6.3 Steel Round Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for extended service life in demanding environments
• Exceptional 60,000 psi tensile strength ensures reliable fastening under high-stress industrial applications
• Optimized Phillips drive performance provides secure tool engagement and reduces stripping during installation
• Class 2A thread fit with UNC coarse threading enables quick assembly and superior vibration resistance
• Full threading along the 3/4" length allows maximum grip and adjustment flexibility in various material thicknesses
• Rockwell B69 hardness rating maintains structural integrity and prevents deformation under load
• Comprehensive regulatory compliance including ASME B18.6.3, RoHS 3, and REACH for global project acceptance

Professional Applications & Engineering Value

These 4-40 UNC zinc-plated steel rounded head screws address critical industrial fastening challenges where corrosion resistance and mechanical reliability are paramount. The combination of zinc-plated steel material and fully threaded coarse UNC design provides excellent protection against environmental degradation while ensuring rapid installation in assembly line operations. The rounded head profile with Phillips drive offers flush mounting capabilities without compromising torque transmission, making these industrial screws ideal for electronics enclosures, machinery panels, and automotive components where vibration resistance and consistent clamping force are essential. The 60,000 psi tensile strength and Rockwell B69 hardness guarantee performance integrity in high-stress applications, reducing maintenance frequency and total cost of ownership.

Specification Summary & Compliance

These rounded head screws feature precise Class 2A thread fit with UNC coarse threading (4-40) maintaining dimensional accuracy per ASME B18.6.3 manufacturing standards. The 3/4" length with fully threaded design ensures consistent engagement across applications. Regulatory compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) certifications, confirming environmental safety and material restrictions adherence for international industrial projects.