S-91253A213 8-32 x 2 1/2" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating, extending service life in demanding industrial environments
• Superior tensile strength (130,000 psi) prevents fastener failure under extreme mechanical loads
• Precision Class 3A thread fit ensures secure mating with nuts and threaded components, reducing assembly issues
• 82° countersink angle with standard flat head profile provides flush surface finishing for streamlined assemblies
• Hex drive (3/32") design delivers maximum torque transmission while minimizing tool slippage
• Rockwell C39 hardness rating maintains thread integrity and drive features through repeated installations
• Partial threading configuration allows for both secure clamping and adjustment flexibility in assemblies

Professional Applications & Engineering Value

These 8-32 UNC flat head screws deliver critical performance advantages for industrial equipment, machinery assembly, and structural frameworks where vibration resistance and long-term reliability are paramount. The black-oxide alloy steel construction provides superior protection against rust and chemical exposure in manufacturing environments, while the coarse thread spacing ensures rapid installation and superior holding power in various substrate materials. The combination of Class 3A thread fit and partial threading allows engineers to achieve precise clamping force control while maintaining alignment accuracy in critical assemblies. These hex drive fasteners are particularly valuable in applications requiring repeated disassembly and reassembly, where drive feature integrity is essential for maintenance operations.

Specification Summary & Compliance

This 2 1/2" flat head screw features precision UNC coarse threads with Class 3A fit tolerances, manufactured to ASTM F835 specifications for consistent quality and performance. The product maintains full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring suitability for global industrial applications. Thread specifications include right-hand direction with minimum 7/8" thread length, providing reliable engagement in various material thicknesses while maintaining the structural benefits of partial threading.