S-98070A130 4-40 x 3/8" Sealing Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Reliable sealing performance with a silicone rubber O-ring that maintains integrity across extreme temperatures from -150° to 500° F, preventing leaks in harsh environments.
• Exceptional corrosion resistance due to 18-8 stainless steel construction and passivated finish, ensuring long-term durability and reduced maintenance.
• High-pressure capability withstands up to 20,000 psi, making it suitable for demanding industrial applications where pressure integrity is critical.
• Precise thread engagement with Class 2A UNC coarse threads and full threading, providing secure fastening and easy installation in various materials.
• Flush mounting design with a standard flat head and 100° countersink angle, allowing for a smooth surface finish and reduced protrusion in assembled parts.
• Broad regulatory compliance including RoHS 3 and REACH, ensuring environmental safety and suitability for global industrial supply chains.
• Optimized drive efficiency featuring a Phillips No. 1 drive for straightforward installation with common tools, minimizing assembly time and errors.

Professional Applications & Engineering Value

This 4-40 UNC flat head Phillips screw is engineered to address critical sealing and corrosion challenges in industrial settings. Constructed from 18-8 stainless steel with a passivated finish, it resists oxidation and chemical exposure, extending service life in moist or aggressive environments. The integrated silicone rubber O-ring ensures a tight seal against fluids and gases, capable of operating in temperature extremes from -150° to 500° F. Ideal for applications in high-pressure systems, such as hydraulic assemblies, pneumatic controls, and automotive components, this screw prevents leakage under pressures up to 20,000 psi. Its fully threaded coarse UNC design and Class 2A thread fit facilitate quick, reliable installation in pre-tapped holes, reducing the risk of cross-threading and enhancing assembly efficiency for industrial fasteners in machinery, enclosures, and fluid handling equipment.

Specification Summary & Compliance

This screw adheres to precise dimensional standards, including UNC coarse threads with a Class 2A thread fit for consistent engagement and tolerance. Key specifications include a 3/8" length, 4-40 thread size, and a maximum hole diameter of 0.129". It complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free from hazardous substances and suitable for use in regulated industries. The manufacturing process emphasizes quality control to meet industrial fastener requirements for strength and reliability.