S-90211A301 3/8"-16 x 2" SAE J429 Left-Hand Threaded High-Strength Steel Hex Head Screws

Key Features & Benefits at a Glance

• Maximum load-bearing capacity with 150,000 PSI tensile strength and Rockwell C33 hardness for reliable performance in high-stress environments
• Superior corrosion resistance through zinc yellow-chromate plating that protects against rust and extends service life in harsh conditions
• Precise thread engagement with Class 3A thread fit ensuring secure fastening and vibration resistance in critical assemblies
• Left-hand threading design providing specialized counter-rotation security for applications where standard right-hand threads would loosen
• Heavy-duty construction meeting Grade 8 specifications for the most demanding industrial and machinery applications
• Full threading coverage along the entire 2" length for maximum grip strength and uniform stress distribution
• External hex drive compatibility with standard 9/16" wrench sizes for easy installation and removal with common tools

Professional Applications & Engineering Value

This Grade 8 left hand hex head screw delivers exceptional engineering value through its specialized left-hand UNC coarse threading and zinc yellow-chromate plating. The combination addresses critical industrial challenges where reverse-thread applications prevent accidental loosening from rotational forces. The 3/8"-16 thread size with coarse spacing provides excellent engagement in softer materials while resisting vibration-induced failure. The external hex drive design ensures reliable torque application without stripping, while the steel construction with precise Class 3A thread fit maintains dimensional stability under extreme loads. These characteristics make it ideal for heavy machinery, automotive systems, and industrial equipment where high tensile strength and corrosion resistance are paramount for operational safety and longevity.

Specification Summary & Compliance

This fastener features 3/8"-16 UNC coarse threading with Class 3A thread fit for precision engagement, manufactured to SAE J429 specifications for Grade 8 fasteners. The 2" length provides full threading coverage with exact dimensional consistency. The zinc yellow-chromate plating offers superior corrosion protection while maintaining compliance with industrial standards. All materials and manufacturing processes adhere to recognized industrial specifications for quality assurance and performance reliability in demanding applications.