S-92785A118 4-40 x 3/8" ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction, ideal for harsh environments and extended service life
• Exceptional holding power provided by the 90° cone point design, ensuring a secure and permanent grip on components
• High-strength performance with Rockwell B80 hardness, offering reliable resistance to wear and deformation
• Precise and secure fastening guaranteed by the Class 3A thread fit, minimizing the risk of loosening under vibration
• Easy installation in confined spaces with the compact, headless design and 0.050" hex drive
• Broad industrial compatibility through UNC coarse threading and right-hand direction, suitable for common assembly applications
• Regulatory peace of mind with compliance to ASME B18.3, RoHS 3, and REACH standards

Professional Applications & Engineering Value

This 4-40 UNC set screw is engineered to solve critical challenges in precision assembly and machinery. The 18-8 Stainless Steel material provides excellent resistance to rust and oxidation, making it suitable for applications in moist or chemically aggressive environments, such as marine equipment, food processing machinery, and outdoor industrial fixtures. The headless design with a hex drive allows for flush mounting, preventing interference in compact assemblies while enabling high torque application. The 90° cone point bites firmly into shafts or hubs, effectively resisting rotational forces and axial movement—a common failure point in dynamic systems. By combining a Class 3A thread fit with coarse UNC threading, this fastener ensures quick installation and reliable performance in high-vibration settings, from motor mounts to precision instruments, enhancing overall equipment durability and safety.

Specification Summary & Compliance

This set screw adheres to precise dimensional standards, including a Class 3A thread fit for superior tolerance control and the UNC coarse thread series (4-40 size). Manufacturing and quality are governed by ASME B18.3 specifications. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free of restricted hazardous substances and safe for use in regulated markets.