S-92210A110 4-40 x 1/2" ASME B18.3 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish, ensuring long-term reliability in harsh environments
• Exceptional holding power from 70,000 psi tensile strength and Rockwell B55 hardness, providing secure fastening under heavy loads
• Precision thread engagement with Class 3A fit and UNC coarse threads, enabling quick installation and vibration resistance
• Flush mounting capability with standard 82° countersink angle and flat head design, creating smooth surface finishes
• Easy installation and removal using standard 1/16" hex drive tools, reducing assembly time and maintenance costs
• Full regulatory compliance meeting ASME B18.3, RoHS 3, and REACH standards, ensuring global acceptance and environmental safety
• Complete thread coverage along the entire 1/2" length, maximizing grip strength and load distribution

Professional Applications & Engineering Value

These 4-40 UNC flat head screws deliver critical engineering advantages where corrosion resistance and structural integrity are paramount. The 18-8 stainless steel composition combined with passivated finish creates a protective barrier against chemical exposure and atmospheric corrosion, making them ideal for marine equipment, food processing machinery, and outdoor industrial applications. The Class 3A thread fit ensures precise mating with corresponding nuts and tapped holes, eliminating play and maintaining alignment in precision assemblies. With 70,000 psi tensile strength and fully threaded design, these flat head screws distribute clamping forces evenly, preventing stress concentration and material deformation. The 82° countersink angle allows seamless integration into machined surfaces, providing aerodynamic profiles in aerospace components and hygienic surfaces in medical devices.

Specification Summary & Compliance

Manufactured to exacting standards with Class 3A thread fit precision and UNC coarse thread spacing for optimal engagement. These flat head screws comply with ASME B18.3 dimensional specifications and feature right-hand threading with 0.112" thread diameter. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations ensures safe use across global markets. The 1/2" length and fully threaded construction maintain consistent performance in demanding industrial applications.