S-90390A117 1/4"-20 x 5" Tapping Screws

Key Features & Benefits at a Glance

• Superior thread cutting performance in aluminum, brass, cast iron, and sheet metal without pre-tapping, reducing installation time and labor costs
• Enhanced corrosion resistance with black-phosphate steel construction for extended service life in demanding industrial environments
• Maximum torque transmission through T30 Torx drive design, minimizing cam-out and tool slippage during high-torque applications
• Flush installation capability with 82° countersink angle and flat head profile for smooth surface finishes in visible applications
• Rapid fastening efficiency with fully threaded coarse UNC spacing, providing quick engagement and strong holding power
• Heavy-duty 5-inch length offers deep penetration and secure fastening in thick materials and structural applications
• Type F thread cutting design ensures reliable thread formation and vibration resistance in various metal substrates

Professional Applications & Engineering Value

These 1/4-20 UNC T30 flat head tapping screws deliver exceptional engineering value by solving critical fastening challenges in metal fabrication and assembly. The black-phosphate steel construction provides essential corrosion protection while maintaining high tensile strength for heavy-duty industrial applications. The specialized thread cutting design (Type F) creates precise mating threads in aluminum, brass, cast iron, and sheet metal without requiring pre-tapped holes, significantly reducing assembly time and eliminating tap breakage risks. The T30 Torx drive system ensures reliable torque transmission in high-vibration environments, while the 82° countersink angle enables flush mounting for aerodynamic and aesthetic requirements. These fully threaded coarse spacing screws are engineered for rapid installation in structural frameworks, machinery enclosures, and metal building components where vibration resistance and pull-out strength are critical.

Specification Summary & Compliance

Manufactured to precise UNC coarse thread standards with 1/4"-20 thread size and Class 2A tolerance for consistent fit and performance. These Type F thread cutting screws feature standard flat head profile with 0.477" head diameter and 5" fully threaded length. Compliant with industry standards for thread cutting fasteners and suitable for use with No. 1 drill bit (0.228" diameter) for proper hole preparation. Meets relevant industrial specifications for metal fastening applications and manufactured under quality systems ensuring dimensional accuracy and performance reliability.