S-92210A432 1/4"-28 x 3 1/2" ASME B18.3 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction and passivated finish, ideal for harsh environments
• Exceptional tensile strength of 70,000 psi ensures reliable performance under high-stress applications
• Precision Class 3A thread fit guarantees secure, vibration-resistant connections with minimal risk of loosening
• Optimized flush mounting with 82° countersink angle and flat head design for smooth, unobtrusive surface finishes
• Enhanced torque transmission via 5/32" hex drive, preventing stripping and enabling efficient installation
• Full threading along the 3 1/2" length provides maximum grip and adjustability in deep or variable material thicknesses
• Compliance with ASME B18.3, RoHS 3, and REACH ensures adherence to rigorous industrial safety and environmental standards

Professional Applications & Engineering Value

This 1/4"-28 UNF flat head screw is engineered to address critical challenges in industrial assembly, where corrosion resistance and structural integrity are paramount. The 18-8 Stainless Steel material, combined with a passivated finish, effectively resists oxidation and chemical exposure, making it suitable for marine, chemical processing, and outdoor equipment. The fine UNF thread and Class 3A fit provide superior holding power in precision machinery, reducing the risk of thread failure under dynamic loads. Its flat head with 82° countersink ensures a seamless fit in countersunk holes, preventing protrusions that could interfere with moving parts or aesthetic requirements. Commonly used in aerospace, automotive, and heavy machinery, this screw delivers reliable fastening in applications demanding high tensile strength and long-term durability.

Specification Summary & Compliance

This screw features a 1/4"-28 UNF fine thread with Class 3A thread fit for precise, tight tolerances. It is manufactured in accordance with ASME B18.3 specifications, ensuring dimensional accuracy and performance reliability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and safe for industrial use across regulated markets.