S-90128A106 4-40 x 1/4" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance under high-stress conditions, reducing the risk of fastener failure in demanding applications.
• Zinc-plated alloy steel construction provides excellent corrosion resistance, extending service life and maintaining integrity in harsh industrial environments.
• Class 3A thread fit offers superior precision and tighter tolerances for secure, vibration-resistant assemblies with minimal backlash.
• Hex socket drive design allows for high-torque installation and easy access in confined spaces, improving assembly efficiency and reducing tool slippage.
• Fully threaded UNC coarse thread enables faster installation and stronger holding power in a wide range of materials, saving time during production.
• ASTM A574 compliance guarantees consistent quality and mechanical properties, ensuring reliability for critical engineering applications.
• RoHS 3 and REACH compliance makes these screws suitable for global markets and environmentally sensitive applications without regulatory concerns.

Professional Applications & Engineering Value

These 4-40 UNC socket head cap screws are engineered to address common industrial challenges such as vibration loosening, corrosion degradation, and assembly precision. The zinc-plated alloy steel material combined with Rockwell C37 hardness provides optimal durability against wear and environmental exposure, making them ideal for machinery, automotive components, and electronic enclosures. The coarse thread design ensures quick installation and strong grip in various substrates, while the hex drive facilitates secure tightening in limited-access areas. By meeting rigorous ASTM A574 specifications, these screws deliver consistent performance in high-stress applications, reducing maintenance needs and enhancing operational reliability for OEMs and maintenance teams.

Specification Summary & Compliance

This product features precise Class 3A thread fit with UNC coarse threads and a right-hand thread direction, ensuring accurate engagement and compatibility with standard components. Manufactured to ASTM A574 standards, it guarantees dimensional consistency and mechanical properties. Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) confirms adherence to environmental and safety regulations, making it suitable for international industrial use without hazardous substance restrictions.