S-92805A378 1/4"-20 x 5/8" ASME B18.3, ASTM F879, MIL-DTL-18240 Stainless Steel Thread-Locking Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Permanent vibration resistance with integrated nylon patch thread locker that maintains secure fastening in high-stress environments
• Superior corrosion protection through 18-8 stainless steel construction for extended service life in harsh conditions
• High-strength performance with 70,000 psi tensile strength and Rockwell B55 hardness for demanding industrial applications
• Reliable temperature stability with locking effectiveness maintained across a wide range from -65° to 250° F
• Precision thread engagement through Class 3A thread fit ensuring consistent, secure mating with components
• Optimized drive efficiency with hex drive design providing superior torque transmission and installation control
• Broad regulatory compliance meeting ASME B18.3, ASTM F879, and MIL-DTL-18240 standards for quality assurance

Professional Applications & Engineering Value

This nylon patch locking flat head screw delivers critical vibration resistance where conventional fasteners fail. The 18-8 stainless steel construction provides exceptional corrosion resistance for harsh environments including marine, chemical processing, and outdoor applications. The UNC coarse thread with Class 3A fit ensures rapid installation and reliable engagement in various materials, while the flat head design with 82° countersink angle creates flush surfaces for streamlined assemblies. The permanent nylon patch thread locker eliminates the need for secondary locking mechanisms, reducing assembly time and maintenance requirements in machinery, equipment manufacturing, and structural applications where vibration-induced loosening poses operational risks.

Specification Summary & Compliance

This fastener features precision 1/4"-20 UNC coarse threads with Class 3A thread fit for superior dimensional accuracy and engagement. Manufacturing complies with ASME B18.3, ASTM F879, and MIL-DTL-18240 specifications ensuring consistent quality and performance. The product is fully RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant, meeting current environmental regulations for industrial use. The fully threaded design provides maximum grip length while the hex drive configuration enables efficient installation with standard tools.