S-91255A127 5-40 x 5/16" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 120,000 psi ensures reliable performance under high-stress industrial applications
• Superior corrosion resistance with black-oxide coating on alloy steel for extended service life in demanding environments
• Precision Class 3A thread fit guarantees secure fastening and vibration resistance in critical assemblies
• Optimized torque transmission through 5/64" hex drive design prevents stripping and enables efficient installation
• Full threading capability provides maximum engagement depth and consistent clamping force across applications
• Rounded button head profile offers low-profile installation while maintaining high Rockwell C39 hardness for durability
• Industry-standard compliance with ASME B18.3 and ASTM F835 ensures consistent quality and interchangeability

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these 5-40 UNC rounded head screws solve critical fastening challenges where vibration resistance and consistent clamping force are paramount. The black-oxide alloy steel construction provides superior corrosion protection in manufacturing environments, while the Class 3A thread fit maintains precision alignment in automated assembly systems. The combination of fully threaded design and coarse UNC threading ensures rapid installation and reliable performance in machinery, equipment frames, and structural components where 120,000 psi tensile strength prevents joint failure under dynamic loads.

Specification Summary & Compliance

Manufactured to exacting Class 3A thread tolerances with UNC coarse thread specifications and right-hand threading. Compliant with ASME B18.3 dimensional standards and ASTM F835 material specifications. Meets environmental regulations including RoHS 3 (2015/863/EU) compliance and REACH (EC 1907/2006) requirements for industrial use.