S-90211A298 3/8"-16 x 1 3/4" 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 Grade 8 classification for critical structural applications
• Superior corrosion resistance through zinc yellow-chromate plating that withstands harsh industrial environments
• Precise thread engagement with Class 3A fit ensuring reliable fastening in high-vibration settings
• Enhanced torque transmission via external hex drive design that prevents tool slippage during installation
• Optimized for reverse-thread applications with left-hand threading for specialized machinery and safety-critical assemblies
• Exceptional durability backed by Rockwell C33 hardness rating for long-term performance under stress
• Industry-standard compliance meeting SAE J429 specifications for quality assurance in automotive and industrial sectors

Professional Applications & Engineering Value

These Grade 8 hex head screws with left-hand UNC threads provide engineered solutions for applications where conventional right-hand threads would loosen under rotational forces. The 3/8"-16 coarse thread spacing delivers rapid installation while maintaining holding power in soft materials or cast components. The zinc yellow-chromate finish creates a protective barrier against oxidation and chemical exposure, extending service life in manufacturing equipment, automotive assemblies, and heavy machinery. With full threading along the 1 3/4" length, these fasteners distribute clamping force evenly across the entire engagement area, preventing stress concentration points that lead to joint failure. The external hex drive accommodates standard wrenching tools for secure installation in confined spaces where socket clearance is limited.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 3A thread fit for superior engagement in tapped holes. The 3/8"-16 UNC coarse thread profile ensures compatibility with standard mating components. Meets SAE J429 specifications for material composition and mechanical properties, with Rockwell C33 hardness and 150,000 psi tensile strength verification. The zinc yellow-chromate plating provides corrosion protection while maintaining compliance with industrial fastener requirements for heavy-duty applications.