S-91257A469 3/8"-24 x 5 3/4" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 psi tensile strength for reliable performance in high-stress applications
• Superior corrosion resistance through zinc yellow-chromate plating, extending service life in harsh environments
• Precision fine threading (3/8"-24 UNF) ensures secure, vibration-resistant connections in critical assemblies
• Optimized partial threading design provides maximum grip length while reducing weight and material usage
• Heavy-duty Grade 8 classification guarantees consistent mechanical properties and Rockwell C33 hardness
• Standard-compliant manufacturing meeting ASME B18.2.1/SAE J429 specifications for interchangeability and quality assurance
• External hex drive compatibility with common industrial tools for efficient installation and maintenance

Professional Applications & Engineering Value

This Grade 8 hex head screw delivers critical engineering solutions for industrial applications where high-strength fastening and corrosion resistance are paramount. The 3/8"-24 UNF fine thread configuration provides superior resistance to vibrational loosening in machinery, automotive, and structural applications. The zinc yellow-chromate plating creates a protective barrier against oxidation and chemical exposure, significantly extending service life in demanding environments. The partially threaded design concentrates the fastener's strength where it's needed most while allowing for precise clamping force distribution. These steel fasteners are engineered to maintain integrity under extreme loads, making them ideal for heavy equipment, construction projects, and industrial machinery requiring Class 2A thread fit precision and reliable performance.

Specification Summary & Compliance

This fastener maintains Class 2A thread fit tolerances with 3/8"-24 UNF fine threading and partial threading extending to a minimum of 1". Manufactured in compliance with ASME B18.2.1 and SAE J429 standards, ensuring dimensional accuracy and mechanical properties. The Grade 8 classification guarantees Rockwell C33 hardness and 150,000 psi tensile strength. The zinc yellow-chromate plating provides corrosion protection while meeting industry requirements for surface treatments. All materials and processes conform to relevant industrial specifications for consistent quality and performance.