S-93310A335 1/4"-20 x 5/16" ASME B18.3, ASTM F879, MIL-DTL-18240 Thread-Locking Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Permanent vibration resistance with nylon patch thread locking that maintains secure fastening from -70° to 250° F, preventing loosening in dynamic environments
• Superior corrosion resistance thanks to 18-8 Stainless Steel construction, ideal for harsh industrial and outdoor applications
• High-strength performance with 70,000 psi tensile strength and Rockwell B55 hardness for demanding mechanical assemblies
• Precise thread engagement with Class 3A UNC coarse threads ensuring reliable installation and consistent clamping force
• Easy installation and removal with 5/32" hex drive design providing positive torque transmission and reduced tool slippage
• Full thread coverage along the 5/16" length maximizes grip range and distribution of load across connected components
• Regulatory compliance assurance meeting ASME B18.3, ASTM F879, and MIL-DTL-18240 standards for quality and reliability

Professional Applications & Engineering Value

Engineered for critical industrial applications where vibration resistance and corrosion protection are paramount, these 1/4-20 UNC nylon patch lock screws solve common fastening failures in machinery, automotive, and electrical enclosures. The 18-8 Stainless Steel construction provides excellent durability against moisture and chemicals, while the nylon patch thread locker creates a permanent locking mechanism that eliminates the need for separate locking washers or adhesives. The rounded button head design with hex drive offers both aesthetic appeal and practical installation advantages, making these coarse thread screws ideal for production lines requiring efficient assembly and long-term reliability in temperature-fluctuating environments from -70° to 250° F.

Specification Summary & Compliance

These fully threaded 1/4-20 UNC screws feature Class 3A thread fit for precision engagement and are manufactured to ASME B18.3, ASTM F879, and MIL-DTL-18240 specifications. The products are fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, ensuring environmental responsibility and safety standards are met for global industrial applications.