S-91247A637 3/8"-16 x 3 1/4" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 120,000 PSI ensures reliable performance in high-stress industrial applications.
• Zinc plating provides superior corrosion resistance, extending the fastener's lifespan in harsh environments.
• Grade 5 steel construction with Rockwell C25 hardness offers an optimal balance of strength and durability.
• 3/8"-16 UNC coarse thread design allows for faster installation and reduced risk of cross-threading.
• External hex drive and hex head enable secure, high-torque tightening with standard tools.
• Class 2A thread fit ensures consistent, reliable engagement with mating components.
• Partially threaded shank provides unthreaded grip length for enhanced clamping force in assembled joints.

Professional Applications & Engineering Value

This Grade 5 hex head screw is engineered for demanding industrial fastening applications where failure is not an option. The zinc plated steel construction combats corrosion, making it ideal for machinery, structural assemblies, and outdoor equipment. The 3/8"-16 UNC coarse thread and partial threading design prevent loosening under vibration and provide superior clamp load distribution. Its 120,000 PSI tensile strength and Rockwell C25 hardness ensure it can withstand significant shear and tensile forces, solving critical challenges in heavy-duty manufacturing, construction, and automotive sectors where joint integrity is paramount.

Specification Summary & Compliance

This screw features a 3/8"-16 UNC thread with a Class 2A thread fit for standard dimensional accuracy. It is manufactured to meet ASME B18.2.1 and SAE J429 specifications for Grade 5 fasteners. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring it is free from hazardous substances for safe use in global markets.