S-90390A122 5/16"-18 x 1 1/4" Tapping Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-phosphate steel coating that protects against rust in demanding industrial environments
• Enhanced torque transmission through T40 Torx drive design, reducing cam-out and tool slippage during installation
• Efficient thread cutting performance with Type F tapping design that creates precise mating threads in aluminum, brass, cast iron and sheet metal
• Optimal flush mounting with 82° countersink angle and flat head profile that sits perfectly flush with material surfaces
• Maximum holding power through fully threaded design that provides complete engagement along the entire 1 1/4" length
• Simplified installation process with pre-determined 0.29" pilot hole (L drill bit) requirement for consistent, reliable performance
• Wide material compatibility with UNC coarse threads specifically engineered for various metals including cast iron and sheet metal

Professional Applications & Engineering Value

These 5/16"-18 thread cutting screws deliver exceptional engineering value in metal fabrication and assembly applications. The black-phosphate steel construction provides durable corrosion protection while the Type F tapping design with blunt tip ensures reliable thread formation without material splitting. The T40 Torx drive enables high-torque installation in confined spaces, significantly reducing installation time and tool wear. Particularly valuable in aluminum, brass, cast iron, and sheet metal applications, these tapping screws eliminate the need for pre-tapped holes while maintaining UNC coarse thread integrity. The 82° countersink angle ensures flush mounting in standard chamfered holes, creating professional finishes in industrial equipment, machinery, and metal structures.

Specification Summary & Compliance

These thread cutting screws feature 5/16"-18 UNC coarse threads with Class 2A tolerance for precise fit. The fully threaded 1 1/4" length provides complete engagement, while the standard flat head profile with 82° countersink ensures proper seating. Manufactured to industry standards for Type F tapping screws, these fasteners comply with relevant industrial specifications for right-hand thread applications. The black-phosphate surface treatment meets industrial corrosion protection requirements, and the product conforms to RoHS and REACH environmental compliance standards for industrial use.