S-90344A130 4-40 x 1/4" ASTM A574 Socket Head Screws with Flat Washer

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide coating on both screw and washer, ideal for harsh industrial environments.
• Exceptional tensile strength of 170,000 psi ensures reliable performance under high-stress applications.
• Precise Class 3A thread fit provides secure, vibration-resistant fastening with minimal risk of loosening.
• Integrated flat washer distributes load evenly, protecting surfaces and enhancing joint integrity.
• Fully threaded design allows for maximum adjustability and consistent clamping force along the entire length.
• Hex socket drive enables high-torque installation with standard tools, reducing slippage and assembly time.
• Compliance with ASTM A574, RoHS 3, and REACH guarantees material quality and environmental safety for global supply chains.

Professional Applications & Engineering Value

Engineered for demanding industrial settings, this 4-40 UNC thread socket head cap screw combines black-oxide alloy steel with a Rockwell C39 hardness to resist wear and corrosion in applications like machinery assembly, automotive components, and electronic enclosures. The coarse UNC thread and Class 3A fit ensure quick installation and reliable hold in materials prone to vibration, while the integrated flat washer prevents surface damage and distributes stress effectively. Ideal for high-tensile strength requirements, this fastener addresses common issues like galvanic corrosion and thread stripping, providing long-term durability in industrial fastening systems.

Specification Summary & Compliance

This screw features a 4-40 UNC coarse thread with Class 3A precision fit for consistent engagement, a 1/4" length, and fully threaded rod design. Manufactured to ASTM A574 specifications, it ensures high strength and reliability. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting safe and sustainable industrial use.