S-90002A102 1/4"-20 x 5/8" ASME B18.2.1, SAE J429 High-Strength Steel Hex Head Screws with Material Certification

Key Features & Benefits at a Glance

• Maximum load-bearing capability with 150,000 psi tensile strength and Grade 8 classification for critical structural applications
• Superior corrosion resistance through zinc yellow-chromate plating that protects against harsh industrial environments
• Optimized thread engagement with UNC coarse threading and Class 2A fit ensuring reliable installation and vibration resistance
• Enhanced durability from Rockwell C33 hardness providing excellent wear resistance and long service life
• Efficient installation and removal via external hex drive design that accommodates standard tools and prevents stripping
• Full-thread coverage along the 5/8" length for maximum grip and load distribution across the entire fastener
• Industry-standard compliance meeting ASME B18.2.1 and SAE J429 specifications for guaranteed interoperability and quality

Professional Applications & Engineering Value

These Grade 8 hex head screws deliver exceptional engineering value in demanding industrial environments where failure is not an option. The zinc yellow-chromate plated steel construction provides superior corrosion protection for outdoor equipment, machinery, and structural assemblies exposed to moisture and chemicals. The 1/4"-20 UNC coarse thread design with Class 2A fit ensures rapid installation and reliable performance in high-vibration applications such as heavy machinery, automotive systems, and construction equipment. The combination of 150,000 psi tensile strength and Rockwell C33 hardness makes these fully threaded screws ideal for critical connections requiring maximum clamping force and fatigue resistance, while the external hex drive allows for high-torque installation without slippage.

Specification Summary & Compliance

This 1/4"-20 x 5/8" hex head screw features precise Class 2A thread fit tolerances with UNC coarse threading according to standard inch system specifications. Manufacturing and quality control strictly adhere to ASME B18.2.1 and SAE J429 standards, ensuring dimensional accuracy and mechanical properties. The fastener meets industry requirements for Grade 8 strength classification with verified 150,000 psi tensile strength and Rockwell C33 hardness testing. The zinc yellow-chromate plating provides RoHS and REACH compliant corrosion protection for industrial applications.