S-98164A543 1/2"-13 x 2 1/2" ASME B18.3, ASTM F879 Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh chemical and marine environments
• Superior load-bearing capability thanks to 70,000 psi tensile strength and Rockwell B55 hardness for reliable performance under stress
• Precise, secure fastening ensured by Class 3A thread fit and UNC coarse spacing, reducing cross-threading risks
• Efficient installation and removal with 5/16" hex drive, providing excellent torque transfer and tool grip
• Full-thread engagement along the 2 1/2" length for maximum holding power in deep applications
• Rounded button head design offers a low-profile, finished appearance while minimizing snagging hazards
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH for guaranteed quality and environmental safety

Professional Applications & Engineering Value

Engineered for demanding industrial settings, this 316 stainless steel rounded head screw delivers outstanding performance in corrosive environments like chemical processing, marine equipment, and food-grade facilities. The passivated finish enhances the natural corrosion resistance of 316 stainless, preventing pitting and extending service life in high-moisture or acidic conditions. With a UNC coarse thread and Class 3A fit, it ensures rapid assembly and reliable clamping force, reducing installation time while maintaining vibration resistance. The combination of 70,000 psi tensile strength and fully threaded design provides uniform stress distribution, making it ideal for structural applications where load integrity is critical. Its 5/16" hex drive allows for high-torque installation with standard tools, streamlining maintenance in confined spaces.

Specification Summary & Compliance

This screw features precision UNC 1/2"-13 coarse threads with Class 3A tolerance for consistent fit and performance. Manufacturing adheres to ASME B18.3 specifications (ASTM F879), ensuring dimensional accuracy and mechanical properties. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming absence of restricted substances and supporting sustainable procurement practices.