S-90128A135 1/4"-28 x 3/8" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance in high-stress applications, reducing the risk of fastener failure.
• Superior corrosion resistance from zinc plating protects against rust and environmental degradation, extending service life in harsh conditions.
• Precise Class 3A thread fit guarantees tight, secure connections with minimal backlash, ideal for fine-threaded assemblies requiring high accuracy.
• High hardness rating (Rockwell C37) provides excellent wear resistance, maintaining thread integrity through repeated use and adjustments.
• Hex socket drive design allows for easy installation and removal with standard tools, even in confined spaces, improving assembly efficiency.
• Full threading along the 3/8" length offers maximum grip and adjustability, ensuring uniform clamping force across the entire fastener.
• Compliance with ASTM A574, RoHS 3, and REACH ensures material quality and environmental safety, meeting rigorous industrial and regulatory standards.

Professional Applications & Engineering Value

This zinc-plated alloy steel socket head cap screw is engineered to address critical challenges in precision machinery, automotive systems, and heavy-duty equipment. Its 1/4"-28 UNF fine thread and Class 3A fit provide exceptional vibration resistance and sealing capabilities, preventing loosening in dynamic environments. The combination of 170,000 psi tensile strength and Rockwell C37 hardness ensures durability under cyclic loads, reducing maintenance needs. The zinc plating offers reliable corrosion protection, making it suitable for outdoor or chemically exposed settings. Ideal for applications demanding high clamp load and fine-thread precision, this screw enhances assembly reliability and longevity in industrial fastening solutions.

Specification Summary & Compliance

This socket head cap screw features a 1/4"-28 UNF fine thread with Class 3A tolerance for precise fit, and is fully threaded along its 3/8" length. It meets ASTM A574 specifications for high-strength socket head cap screws, ensuring consistent manufacturing quality. The product is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and safe for various industrial applications.