S-90211A372 5/8"-11 x 4" SAE J429 Left-Hand Threaded High-Strength Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 PSI tensile strength and Grade 8 classification for reliable performance in high-stress industrial environments
• Superior corrosion protection through zinc yellow-chromate plating that extends service life in harsh operating conditions
• Precise thread engagement with Class 3A fit and UNC coarse threads ensuring secure fastening and vibration resistance
• Left-hand threading design providing specialized solutions for counter-rotational applications and machinery safety
• Full-threaded construction offering maximum grip length and uniform stress distribution across the entire fastener
• Heavy-duty material performance with Rockwell C33 hardness maintaining structural integrity under extreme mechanical loads
• Industry-standard compliance meeting SAE J429 specifications for quality assurance in demanding applications

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these Grade 8 hex head screws deliver critical performance where failure is not an option. The combination of 150,000 PSI tensile strength and Rockwell C33 hardness ensures reliable operation in high-vibration environments such as heavy machinery, construction equipment, and automotive assemblies. The left-hand UNC coarse thread configuration provides specialized solutions for applications requiring reverse-threading safety, while the zinc yellow-chromate plating offers superior corrosion resistance in outdoor or chemically aggressive settings. The external hex drive and fully threaded design enable efficient installation and maximum clamping force distribution, making these fasteners ideal for structural connections, equipment manufacturing, and maintenance operations where industrial strength and long-term reliability are paramount.

Specification Summary & Compliance

This 5/8"-11 UNC hex head screw features precision Class 3A thread fit with coarse thread spacing and left-hand thread direction. Manufactured from high-strength steel with zinc yellow-chromate plating finish, the fastener maintains dimensional accuracy per inch system requirements. The product complies with SAE J429 specifications for Grade 8 fasteners, ensuring consistent performance in industrial applications. With a length of 4 inches and full threading, this heavy-duty screw delivers reliable mechanical properties including the specified tensile strength and hardness ratings for professional use.