S-90550A140 2-56 x 1/2" ASME B18.3, ASTM F879, MIL-DTL-18240 Venting Stainless Steel Hex-Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction, ensuring long-term reliability in harsh environments
• Enhanced torque transmission via 0.050" hex drive design, preventing cam-out and enabling secure installation
• Precise thread engagement with Class 3A fit and UNC coarse threads, delivering consistent clamping force and vibration resistance
• Optimized flush mounting with standard 82° flat head profile, ideal for applications requiring smooth surface finishes
• Pressure equalization capability through integrated venting (0.028" diameter), preventing fluid or gas buildup in sealed assemblies
• Full thread coverage across the 1/2" length, maximizing grip range and load distribution
• Regulatory compliance assurance meeting RoHS 3 and REACH standards, suitable for global industrial markets

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these 2-56 UNC flat head screws address critical assembly challenges through their 18-8 stainless steel composition and specialized design. The hex drive configuration provides superior torque resistance compared to slotted alternatives, reducing installation damage in high-volume production environments. The fully threaded construction ensures maximum thread engagement in thin materials, while the vented feature prevents pressure differential issues in enclosed systems such as instrumentation housings or fluid control devices. With coarse thread spacing enhancing assembly speed and Class 3A thread fit maintaining precision, these fasteners deliver reliable performance in aerospace components, electronic enclosures, and machinery where corrosion-resistant fasteners are essential for operational integrity.

Specification Summary & Compliance

Manufactured to exacting ASME B18.3, ASTM F879, and MIL-DTL-18240 specifications, these screws guarantee dimensional accuracy with Class 3A thread fit tolerances and standardized 82° flat head profile. The UNC thread form with coarse spacing ensures compatibility with industry-standard components. Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations confirms environmental responsibility and material safety for international supply chains.