S-90019A340 3/8"-16 x 1 1/4" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Thread-Locking Hex Head Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking with nylon patch thread locker maintains secure connections in high-stress environments
• Exceptional strength performance with Grade 8 rating and 150,000 psi tensile strength for heavy-duty applications
• Superior corrosion protection through zinc yellow-chromate plating extends service life in harsh conditions
• Reliable temperature performance with thread locker effective from -55° to 250°F for diverse operating environments
• Precise thread engagement with UNC coarse pattern and Class 2A fit ensures consistent installation and removal
• Optimized torque transmission through external hex drive design for efficient assembly and disassembly
• Full thread coverage along the 1 1/4" length provides maximum grip and load distribution

Professional Applications & Engineering Value

These Grade 8 hex head screws with nylon patch thread locking deliver critical vibration resistance in demanding industrial applications where joint integrity is paramount. The zinc yellow-chromate plated steel construction provides excellent corrosion protection for outdoor equipment, machinery, and automotive assemblies exposed to harsh environments. The UNC coarse thread pattern combined with Class 2A fit ensures reliable engagement in both soft and hard materials, while the 150,000 psi tensile strength supports heavy structural loads. The temperature-resistant nylon patch maintains locking effectiveness across extreme thermal cycles from -55° to 250°F, making these fully threaded fasteners ideal for construction equipment, industrial machinery, and transportation applications where vibration loosening poses significant operational risks.

Specification Summary & Compliance

This 3/8"-16 hex head screw features precision UNC coarse threading with Class 2A fit for consistent installation performance. Manufactured to meet ASME B18.2.1 and SAE J429 specifications, ensuring dimensional accuracy and mechanical properties compliance. The fastener achieves Grade 8 strength classification with Rockwell C33 hardness and 150,000 psi tensile strength. The thread locker system utilizes a nylon patch applied to the threads for reliable vibration resistance. Compliant with industry standards for heavy-duty mechanical fasteners in industrial and construction applications.