S-90602A243 1/4"-20 x 2 1/2" IFI 111, SAE J429 High-Strength Grade 8 Steel Flanged Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capability with 150,000 psi tensile strength for reliable performance in high-stress applications
• Superior corrosion resistance thanks to zinc yellow-chromate plating that extends service life in harsh environments
• Optimized thread engagement with UNC coarse threads and Class 2A fit ensuring secure fastening and vibration resistance
• Enhanced driving efficiency through external hex drive design that accommodates standard tools for quick installation
• Increased bearing surface area from the integrated flange that distributes load pressure and prevents surface damage
• Precision manufacturing compliance meeting SAE J429/IFI 111 specifications for consistent quality and interchangeability
• Grade 8 reliability with Rockwell C32 hardness providing excellent durability against wear and deformation

Professional Applications & Engineering Value

Engineered for demanding industrial environments, these Grade 8 hex head screws deliver critical performance where failure is not an option. The zinc yellow-chromate plated steel construction provides superior protection against corrosion in outdoor applications, manufacturing facilities, and machinery subjected to harsh conditions. The 1/4"-20 UNC coarse thread configuration ensures rapid assembly while maintaining strong holding power, with partial threading allowing for precise clamp load control. The external hex drive and flanged design combine to create an optimal fastening solution for heavy equipment, structural assemblies, and automotive applications where vibration resistance and repeated disassembly are common requirements. These screws address the critical need for fasteners that maintain integrity under extreme mechanical stress while offering straightforward installation and long-term reliability.

Specification Summary & Compliance

This hex head screw features precise Class 2A thread fit tolerances with UNC coarse thread specifications ensuring proper engagement and interchangeability. Manufacturing complies with SAE J429 standards and IFI 111 specifications, guaranteeing consistent quality and performance metrics. The fastener maintains dimensional accuracy with 1/4"-20 thread size, 2 1/2" length, and partial threading with minimum 3/4" thread length. Material composition and plating meet industry standards for mechanical properties and environmental compliance.