S-90211A428 3/4"-10 x 3" SAE J429 Left-Hand Threaded High-Strength Steel 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 through zinc yellow-chromate plating that protects against harsh industrial environments
• Precise thread engagement with Class 3A thread fit ensuring secure fastening and vibration resistance
• Enhanced durability from Rockwell C33 hardness providing excellent wear resistance and long service life
• Optimized for reverse-thread applications with left-hand UNC coarse threading for specialized machinery and safety-critical installations
• Full compliance with SAE J429 specifications guaranteeing consistent quality and performance standards
• Easy installation and removal with external hex drive and 1 1/8" head width for standard wrench compatibility

Professional Applications & Engineering Value

This Grade 8 hex head screw delivers critical engineering solutions where conventional right-hand threads would loosen under rotational forces. The left-hand UNC coarse threading provides secure fastening in applications involving counter-clockwise rotating machinery, preventing accidental disassembly. The zinc yellow-chromate plating creates a robust barrier against corrosion in demanding environments like manufacturing plants, construction sites, and heavy equipment. With fully threaded design and 3-inch length, it ensures maximum grip length and uniform stress distribution. These industrial screws are engineered for machinery maintenance, automotive assemblies, and structural applications where vibration resistance and 150,000 psi tensile strength are paramount for operational safety and reliability.

Specification Summary & Compliance

Manufactured to Class 3A thread fit tolerances for precise engagement, this fastener meets SAE J429 specifications for dimensional accuracy and mechanical properties. The 3/4"-10 UNC coarse thread pattern ensures compatibility with standard components while the inch system measurements maintain consistency across North American industrial applications. The external hex drive with 1 1/8" head width provides standardized tool interface. Material composition and zinc yellow-chromate plating comply with industry standards for corrosion protection and environmental regulations.