S-90128A137 5/16"-18 x 1 1/8" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc plating that protects against rust in harsh industrial environments
• Exceptional load-bearing capacity with 170,000 psi tensile strength for reliable performance under extreme stress
• Precision thread engagement with Class 3A fit ensuring secure, vibration-resistant connections
• Easy installation and removal using standard 1/4" hex drive tools for efficient maintenance
• Consistent mechanical properties with Rockwell C37 hardness providing excellent wear resistance
• Full thread coverage along the entire 1-1/8" length for maximum grip and holding power
• Regulatory compliance assurance meeting RoHS 3 and REACH environmental standards

Professional Applications & Engineering Value

These zinc-plated alloy steel socket head cap screws deliver critical performance advantages in demanding applications where failure is not an option. The UNC coarse thread design provides superior resistance to vibration loosening while enabling faster assembly in production environments. With 170,000 psi tensile strength and Rockwell C37 hardness, these fasteners maintain structural integrity in heavy machinery, automotive assemblies, and industrial equipment subjected to dynamic loads. The fully threaded configuration ensures maximum engagement in tapped holes or with mating nuts, while the hex socket drive allows for high-torque installation in confined spaces where wrench clearance is limited.

Specification Summary & Compliance

Manufactured to ASTM A574 specifications with Class 3A thread fit for precision tolerance. Features 5/16"-18 UNC coarse threads with right-hand orientation and standard socket head profile. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The zinc-plated alloy steel construction provides consistent mechanical properties across the 1-1/8" length with reliable performance in industrial applications.