S-91211A206 5/8"-11 x 2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Thread-Locking Hex Head Screws

Key Features & Benefits at a Glance

• Maximum Load-Bearing Capacity - Grade 8 classification and 150,000 PSI tensile strength ensure reliable performance in high-stress industrial applications
• Vibration-Resistant Locking - Nylon patch thread locker maintains secure fastening from -55° to 250°F, preventing loosening in dynamic environments
• Superior Corrosion Protection - Zinc yellow-chromate plated steel construction provides excellent resistance to rust and environmental degradation
• Optimized Installation Efficiency - External hex drive and coarse UNC threads enable quick assembly with standard tools while maintaining Class 2A precision
• Enhanced Durability - Rockwell C33 hardness rating ensures long-term wear resistance and structural integrity under repeated stress
• Full Thread Engagement - Completely threaded 2" length allows for maximum grip strength and uniform load distribution
• Industry Compliance Assurance - Meets ASME B18.2.1 and SAE J429 specifications for guaranteed quality and interchangeability

Professional Applications & Engineering Value

Engineered for demanding industrial environments, these Grade 8 hex head screws deliver exceptional performance where vibration resistance and high tensile strength are critical. The zinc yellow-chromate plated steel construction provides superior corrosion protection in harsh conditions, while the nylon patch thread locking technology effectively prevents fastener loosening in machinery, structural assemblies, and heavy equipment applications. The UNC coarse thread pattern with Class 2A fit ensures reliable engagement in both soft and hard materials, making these 5/8"-11 hex screws ideal for construction, manufacturing, and automotive applications where safety and reliability cannot be compromised. The combination of high-strength materials and precision engineering addresses common failure points in industrial fastening systems.

Specification Summary & Compliance

These 5/8"-11 hex head screws feature precise Class 2A thread fit with UNC coarse threading and right-hand direction. Manufactured to meet ASME B18.2.1 and SAE J429 specifications, ensuring dimensional accuracy and mechanical properties compliance. The Grade 8 strength classification guarantees 150,000 PSI tensile strength and Rockwell C33 hardness, while the nylon patch thread locker maintains performance across the specified temperature range of -55° to 250°F.