S-92210A121 4-40 x 2" ASME B18.3, ASTM F879 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance thanks to 18-8 stainless steel construction and passivated finish, ensuring long-term reliability in harsh environments.
• Superior load-bearing capability with a tensile strength of 70,000 psi, providing reliable performance in high-stress applications.
• Precise and secure fastening achieved through Class 3A thread fit and UNC coarse threads, reducing the risk of cross-threading and ensuring consistent clamp load.
• Optimized for flush mounting with a standard 82° countersink angle flat head, creating a smooth, unobtrusive surface finish.
• Efficient installation and removal facilitated by the hex drive, allowing for high torque application with standard tools.
• Full thread engagement along the entire 2" length, offering maximum grip and adjustability in various material thicknesses.
• Compliance with major industry standards including ASME B18.3, RoHS 3, and REACH, ensuring material safety and interoperability.

Professional Applications & Engineering Value

These 4-40 UNC flat head screws are engineered to address critical challenges in industrial assembly, such as vibration loosening and material fatigue. The 18-8 Stainless Steel material, combined with a passivated finish, provides excellent resistance to oxidation and chemical exposure, making them ideal for use in machinery, electronic enclosures, and outdoor equipment. The coarse UNC thread and Class 3A fit ensure rapid installation and a secure hold in softer materials or pre-tapped holes, reducing assembly time and improving joint integrity. Their fully threaded design and hex drive offer versatility and high torque capability, essential for maintenance and production lines where reliability and speed are paramount.

Specification Summary & Compliance

This product adheres to precise dimensional standards with a Class 3A thread fit and UNC coarse thread profile, ensuring high interchangeability and performance. Manufacturing and material specifications meet ASME B18.3. The screws are fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006), confirming they are free from hazardous substances and safe for various industrial and consumer applications.