S-90390A127 5/16"-18 x 5" Tapping Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-phosphate steel coating, extending service life in harsh industrial environments
• High-torque installation capability through T40 Torx drive, preventing cam-out and ensuring secure fastening
• Efficient thread cutting with Type F tapping design, creating precise threads in aluminum, brass, cast iron and sheet metal without pre-tapping
• Optimal material engagement with 5/16"-18 UNC coarse threads, providing exceptional pull-out resistance in soft metals
• Flush surface finishing enabled by standard 82° flat head profile, eliminating protrusions in assembled components
• Full-length threading across the entire 5" length, maximizing grip range and load distribution
• Simplified installation process with matching 0.29" drill bit specification, reducing preparation time and errors

Professional Applications & Engineering Value

These 5/16"-18 T40 flat head tapping screws deliver critical engineering advantages in metal fabrication and assembly operations. The black-phosphate steel construction provides essential corrosion protection where moisture or chemical exposure would compromise ordinary fasteners. The Type F thread cutting design eliminates the need for separate tapping operations, significantly reducing installation time and labor costs in production environments. With their 82° countersink angle and fully threaded 5" length, these screws maintain consistent clamping force across extended joint surfaces in aluminum extrusions, brass fittings, cast iron housings, and sheet metal assemblies. The T40 Torx drive system ensures maximum torque transfer during installation, preventing fastener damage while achieving proper seating in demanding industrial applications.

Specification Summary & Compliance

Manufactured to precise dimensional standards with UNC coarse threads (5/16"-18) and standard flat head profile. The screws feature Class 2A thread tolerances for consistent fit and performance. Compatible with standard 0.29" (L drill size) pilot holes for optimal thread engagement. Manufactured in compliance with industry standards for thread cutting screws and suitable for use in various metal substrates including aluminum, brass, cast iron, and sheet metal applications.