S-95198A275 4-40 x 3/8" ASME B18.3, DIN 912, ISO 4762 Sealing Socket Head Screws

Key Features & Benefits at a Glance

• Superior Sealing Performance: Integrated Buna-N rubber O-ring ensures reliable sealing in demanding environments, preventing leaks and contamination in pressurized systems up to 1500 psi.
• Exceptional Corrosion Resistance: Made from 18-8 Stainless Steel, offering excellent durability and resistance to rust and oxidation in harsh industrial conditions.
• High Tensile Strength: Withstands up to 100,000 psi tensile stress, providing reliable fastening in high-load applications without failure.
• Precision Thread Fit: Class 3A thread fit ensures tight, secure engagement with minimal play, reducing vibration loosening and improving assembly accuracy.
• Wide Temperature Tolerance: O-ring maintains integrity across a broad temperature range from -40° to 225°F, suitable for varied operational environments.
• Easy Installation with Hex Drive: Standard hex socket head allows for quick, secure tightening using common tools, enhancing efficiency in assembly lines.
• Compliance with Global Standards: Meets ASME B18.3, DIN 912, and ISO 4762 specifications, ensuring interoperability and quality in international projects.

Professional Applications & Engineering Value

This 4-40 UNC thread socket head cap screw is engineered to address critical challenges in industrial sealing and fastening. The combination of 18-8 Stainless Steel and a Buna-N rubber O-ring provides a robust solution for applications requiring resistance to moisture, chemicals, and pressure fluctuations. Its coarse UNC thread and Class 3A fit ensure quick, reliable assembly in machinery, automotive, and aerospace components, where vibration resistance and leak prevention are paramount. The fully threaded design and hex drive facilitate easy installation in confined spaces, reducing downtime. Ideal for hydraulic systems, pumps, and enclosures, this screw delivers long-term reliability under high-stress conditions, minimizing maintenance needs and enhancing operational safety.

Specification Summary & Compliance

This screw features precise 4-40 UNC coarse threads with a Class 3A thread fit for high accuracy, manufactured in accordance with ASME B18.3, DIN 912, and ISO 4762 standards. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and adherence to global regulatory requirements for industrial fasteners.