S-90201A225 5/16"-18 x 1 1/4" Extreme-Strength Grade 9 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 180,000 PSI ensures reliable performance in high-stress industrial applications, reducing the risk of fastener failure.
• Superior corrosion resistance with Zinc Yellow-Chromate plating extends service life in harsh environments, minimizing maintenance and replacement costs.
• High hardness rating (Rockwell C38) provides excellent wear resistance, maintaining thread integrity through repeated use and vibration.
• Full threading along the entire 1-1/4" length offers maximum grip and load distribution, enhancing joint stability in heavy-duty assemblies.
• Precise Class 2A thread fit with coarse UNC threading ensures easy installation and secure fastening, saving time during assembly operations.
• External hex drive design allows for high-torque application with standard tools, improving efficiency in mechanical fastening tasks.
• Compliance with RoHS 3 and REACH regulations guarantees environmental safety and material quality, supporting sustainable manufacturing practices.

Professional Applications & Engineering Value

Engineered for demanding industrial environments, these Grade 9 hex head screws deliver critical reliability where failure is not an option. The steel construction combined with 180,000 PSI tensile strength and Rockwell C38 hardness provides exceptional resistance to shear and tensile forces in heavy machinery, structural steel connections, and automotive assemblies. The Zinc Yellow-Chromate plating creates a protective barrier against corrosion in outdoor or chemically exposed settings, while the fully threaded 5/16"-18 UNC coarse thread design ensures maximum engagement in both thick materials and vibration-prone applications. These high-strength fasteners solve common engineering challenges by maintaining clamp load under dynamic stresses, preventing joint loosening in critical industrial hex screw applications where safety and durability are paramount.

Specification Summary & Compliance

This hex head screw features precise Class 2A thread fit with 5/16"-18 UNC coarse thread spacing and right-hand thread direction, manufactured to inch system standards. The fastener meets Grade 9 strength classification with verified mechanical properties including 180,000 PSI tensile strength and Rockwell C38 hardness. Compliance is confirmed with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring restricted substance-free manufacturing for global industrial applications.