S-93878A121 4-40 x 5/8" Tapping Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for extended service life in harsh industrial environments
• Efficient thread forming capability creates strong, permanent threads in steel, aluminum, and other metals without pre-tapping
• Optimized drive performance with No. 1 Phillips head ensuring secure tool engagement and reduced cam-out during installation
• Maximum holding power through fully threaded design and coarse UNC spacing for reliable fastening in demanding applications
• Versatile material compatibility engineered for steel, aluminum, brass, cast iron, and sheet metal assemblies
• Streamlined installation process with precise 0.104" drill bit specification and blunt tip design for accurate positioning
• Enhanced assembly efficiency with standardized 4-40 UNC thread size and right-hand threading for consistent performance

Professional Applications & Engineering Value

These zinc-plated steel tapping screws with 4-40 UNC coarse threading deliver exceptional engineering value in metal fabrication and industrial assembly. The thread forming design (SW type) eliminates the need for separate tapping operations, creating strong, vibration-resistant threads directly in parent materials. This proves particularly valuable in steel frameworks, aluminum enclosures, brass components, cast iron housings, and sheet metal assemblies where traditional fastening methods may compromise material integrity. The fully threaded configuration ensures maximum thread engagement along the entire 5/8" length, while the pan head with No. 1 Phillips drive provides reliable installation torque transfer. This combination addresses critical industrial pain points including reduced assembly time, elimination of loose hardware, and consistent performance in high-vibration environments common to manufacturing equipment, electrical enclosures, and automotive components.

Specification Summary & Compliance

These tapping screws maintain precision UNC thread standards with Class 2A fit tolerances for consistent performance. The manufacturing follows industrial fastening specifications for thread forming screws, ensuring reliable performance in metal applications. The zinc plating provides corrosion protection while maintaining electrical conductivity. The screws are engineered for use with standard 0.104" drill bits (size #37) and comply with industry standards for right-hand threaded fasteners. Materials and finishes meet RoHS and REACH compliance requirements for industrial applications.