S-91306A385 5/16"-18 x 1/2" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with zinc plating that protects against rust and extends service life in demanding environments
• Superior load-bearing capacity with 120,000 psi tensile strength and Rockwell C39 hardness for reliable performance under high stress
• Precise thread engagement through Class 3A thread fit and UNC coarse spacing, ensuring secure fastening and vibration resistance
• Efficient installation with 3/16" hex drive that provides excellent torque transfer and reduces tool slippage
• Full threading coverage along the 1/2" length for maximum grip and uniform stress distribution in assembled components
• Broad regulatory compliance meeting ASME B18.3, ASTM F835, RoHS 3, and REACH standards for safe, quality-assured industrial use
• Versatile rounded button head design that offers a low-profile finish while minimizing surface damage and snagging risks

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these zinc-plated alloy steel rounded head screws deliver exceptional durability where vibration, corrosion, and mechanical stress are common challenges. The Class 3A thread fit and UNC coarse threading provide superior resistance to loosening in machinery, automotive assemblies, and structural frameworks. With a fully threaded design and 120,000 psi tensile strength, they ensure uniform clamping force and integrity in high-load scenarios. The hex drive compatibility allows for quick, secure installation with standard tools, reducing assembly time while maintaining precision. Ideal for OEM manufacturing, equipment maintenance, and construction projects requiring reliable, compliant industrial fasteners.

Specification Summary & Compliance

This screw features precise Class 3A thread fit with UNC coarse spacing (5/16"-18), manufactured to ASME B18.3 and ASTM F835 specifications. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global markets. Dimensions include a 0.547" head diameter, 1/2" length, and 3/16" hex drive for consistent performance in inch-system applications.