S-97972A211 5/16"-18 x 3/4" Extreme-Strength Steel Flanged Hex Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide steel coating, extending service life in harsh industrial environments
• Exceptional 180,000 psi tensile strength ensures reliable performance under heavy loads and vibration
• Rockwell C38 hardness provides excellent wear resistance and durability for repeated use
• Flanged design eliminates need for separate washers, reducing assembly time and component count
• External hex drive allows high torque application with standard tools for secure fastening
• Class 2A thread fit ensures easy assembly while maintaining proper clearance for manufacturing efficiency
• Fully threaded design provides maximum grip length and load distribution across the entire fastener

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these black-oxide steel hex head screws deliver exceptional performance where reliability is critical. The combination of 180,000 psi tensile strength and Rockwell C38 hardness makes them ideal for structural assemblies, machinery frames, and equipment requiring vibration resistance. The 5/16"-18 UNC coarse thread provides excellent engagement in various materials, while the flanged design distributes clamping force evenly, preventing surface damage. The black-oxide finish offers superior corrosion protection in demanding environments, making these external hex drive screws perfect for automotive, construction, and manufacturing applications where high-strength fastening solutions are essential for operational safety and longevity.

Specification Summary & Compliance

This 5/16"-18 UNC hex head screw features Class 2A thread fit per ASME B1.1 standards, ensuring proper clearance and manufacturing tolerance. The coarse thread spacing and 0.3125" thread diameter provide reliable engagement, while the 3/4" length and 5/8" flange diameter deliver optimal fastening performance. Manufactured from high-grade steel with black-oxide surface treatment, these screws meet industry standards for heavy-duty fasteners and comply with RoHS and REACH environmental requirements.