S-90201A547 5/8"-11 x 4 1/2" Extreme-Strength Grade 9 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with Grade 9 classification and 180,000 PSI tensile strength for demanding industrial applications
• Superior corrosion resistance provided by zinc yellow-chromate plating, extending service life in harsh environments
• Optimized thread engagement through Class 2A UNC coarse threads ensuring reliable fastening and vibration resistance
• Enhanced installation efficiency with external hex drive design allowing high torque application and secure tightening
• Reduced material stress concentration through Rockwell C38 hardness balancing strength with controlled brittleness
• Versatile partial threading enabling both clamping and alignment functions in structural assemblies
• Regulatory compliance assurance meeting RoHS 3 and REACH standards for global industrial deployment

Professional Applications & Engineering Value

Engineered for heavy-duty industrial fastening, these Grade 9 hex head screws deliver critical performance in structural steel connections, machinery assembly, and high-vibration environments. The 5/8"-11 UNC coarse thread configuration provides rapid installation while maintaining Class 2A thread fit precision for consistent clamp load distribution. The zinc yellow-chromate plating creates a robust barrier against oxidation and chemical exposure, significantly extending maintenance intervals in manufacturing plants, construction sites, and outdoor installations. With partial threading design, these fasteners effectively combine the grip range of threaded sections with the shear resistance of unthreaded shanks, solving common challenges of joint slippage and stress concentration in high-strength bolting applications.

Specification Summary & Compliance

Manufactured to inch system standards with 5/8"-11 UNC coarse threads maintaining Class 2A thread fit tolerances for precision engagement. The 4 1/2" length with 1 1/2" minimum thread length provides optimal fastening range. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations ensures suitability for global industrial supply chains. Mechanical properties certified to Grade 9 standards with verified 180,000 PSI tensile strength and Rockwell C38 hardness.