S-92360A109 4-40 x 1/2" ASME B18.3, ASTM F835, MIL-DTL-18240 Thread-Locking Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking with integrated nylon patch that maintains secure fastening from -70° to 250° F, preventing loosening in demanding environments
• Exceptional tensile strength rated at 120,000 psi for reliable performance under high-stress industrial applications
• Precision Class 3A thread fit ensures consistent engagement and superior fastening accuracy in critical assemblies
• Durable black-oxide finish on alloy steel provides corrosion resistance and extends service life in harsh conditions
• Hex drive design allows for efficient installation with standard tools while the rounded head offers a clean, finished appearance
• Full threading capability enables maximum grip length and versatile positioning in various material thicknesses
• Industry compliance assurance meeting ASME, ASTM, and military specifications for guaranteed quality and reliability

Professional Applications & Engineering Value

These 4-40 UNC thread screws with nylon patch thread locker deliver critical vibration resistance in industrial machinery, electronic enclosures, and automotive assemblies where constant motion threatens fastener integrity. The black-oxide alloy steel construction combines Rockwell C39 hardness with corrosion protection, addressing both mechanical stress and environmental degradation concerns. The coarse thread design ensures rapid installation and superior holding power in softer materials, while the Class 3A thread fit provides precise tolerance control for repetitive assembly operations. Engineered to maintain locking performance across extreme temperature fluctuations (-70° to 250° F), these rounded head screws eliminate the need for secondary locking components, streamlining production while enhancing reliability in vibration-prone applications.

Specification Summary & Compliance

Manufactured to exacting Class 3A thread fit tolerances with UNC coarse threading (4-40 size) and 1/2" length. Fully compliant with ASME B18.3, ASTM F835, and MIL-DTL-18240 specifications. Meets environmental regulations including RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance. The alloy steel material achieves 120,000 psi tensile strength with Rockwell C39 hardness for durable performance in industrial fastening applications.