S-90434A179 Length 3/8" Tapping Screws

Key Features & Benefits at a Glance

• Superior thread forming in plastics with the TRS tri-lobe shank design, reducing material stress and preventing cracking during installation.
• Enhanced corrosion resistance thanks to the Black Oxide Steel finish, ensuring long-term durability in various environments.
• Secure and flush installation with the standard 82° flat head profile, providing a clean finish and reducing snagging risks.
• Efficient driving with reduced cam-out using the No. 1 Phillips drive, allowing for consistent torque application and faster assembly.
• Reliable fastening in plastic materials due to the fully threaded, blunt tip design, which ensures strong holding power without pre-drilling in many cases.
• Wide compatibility and ease of use with a recommended No. 37 drill bit (0.104" diameter), simplifying the installation process for professionals.
• Compliance with environmental and safety standards, including RoHS 3 and REACH, making it suitable for global industrial applications.

Professional Applications & Engineering Value

This No. 4 TRS tapping screw is precision-engineered for plastic fastening applications, where traditional screws may cause material failure. The thread forming design with a tri-lobe shank cross-section displaces plastic material gently, creating strong, load-bearing threads without chips or debris. This reduces the risk of stress cracking in brittle plastics, common in electronics, automotive trim, and consumer goods assemblies. Made from Black Oxide Steel, it offers improved resistance to rust and wear, while the flat head with an 82° countersink ensures a seamless finish. The No. 1 Phillips drive provides reliable torque transfer, minimizing tool slippage and enhancing productivity in high-volume manufacturing settings.

Specification Summary & Compliance

This screw adheres to standard inch measurements with a thread diameter of 0.112" and approximately 20 threads per inch, ensuring precise fits in plastic components. It is fully threaded and designed for right-hand installation, with manufacturing consistency for repeatable performance. The product complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free of hazardous substances and suitable for use in regulated industries.