S-90390A545 1/4"-20 x 1 1/2" Tapping Screws

Key Features & Benefits at a Glance

• Superior thread cutting performance with Type F tapping design ensures clean, secure threads in aluminum, brass, cast iron, and sheet metal without pre-tapping.
• Enhanced corrosion resistance from black phosphate steel coating protects against rust in demanding industrial environments.
• High-torque capability with T30 Torx drive prevents cam-out and allows for greater tightening force compared to standard drives.
• Optimal material engagement through fully threaded 1-1/2" length and UNC coarse thread provides maximum holding power in various substrates.
• Flush installation with 82° countersink angle and standard flat head profile for a smooth, professional finish.
• Durable blunt tip design reduces risk of cross-threading and improves alignment during installation.
• Wide compatibility with No. 1 drill bit (0.228" diameter) for precise pilot holes in recommended materials.

Professional Applications & Engineering Value

These 1/4-20 T30 Torx flat head tapping screws are engineered to solve common fastening challenges in metalworking and fabrication. The black phosphate steel construction combined with thread cutting design eliminates the need for separate tapping operations, significantly reducing assembly time in aluminum, brass, cast iron, and sheet metal applications. The UNC coarse thread provides excellent pull-out resistance in softer materials, while the T30 Torx drive ensures reliable installation without tool slippage under high torque conditions. The 82° countersink angle and fully threaded configuration deliver consistent clamping force across the entire engagement length, making these self-tapping screws ideal for HVAC systems, electrical enclosures, machinery assembly, and other industrial applications requiring vibration-resistant, permanent fastening solutions.

Specification Summary & Compliance

These screws feature 1/4"-20 UNC coarse threads with standard Class 2A tolerance for consistent fit. The right-hand thread direction and fully threaded design ensure maximum engagement. Manufacturing complies with industry standards for thread cutting screws (Type F) and includes RoHS and REACH compliance for environmental safety. The black phosphate surface treatment meets corrosion resistance requirements for industrial applications.