S-95198A279 4-40 x 7/8" 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 up to 1500 psi, preventing leaks in high-pressure applications.
• Exceptional Corrosion Resistance: Made from 18-8 stainless steel, offering excellent durability in harsh environments and reducing maintenance needs.
• High Tensile Strength: Withstands up to 100,000 psi tensile strength, providing reliable fastening under heavy loads and vibrations.
• Precise Thread Fit: Class 3A UNC coarse threads ensure tight, secure connections with minimal risk of loosening in industrial assemblies.
• Wide Temperature Tolerance: O-ring functions effectively from -40° to 225°F, making it suitable for diverse operating conditions.
• Easy Installation: Hex socket drive allows for quick, tool-friendly installation with standard 3/32" hex keys, saving time on the assembly line.
• Full Compliance Assurance: Meets ASME B18.3, DIN 912, and ISO 4762 standards, ensuring interchangeability and reliability in global applications.

Professional Applications & Engineering Value

This 4-40 UNC thread socket head cap screw is engineered to address critical sealing and durability challenges in industrial settings. The 18-8 stainless steel construction provides inherent corrosion resistance, ideal for machinery exposed to moisture, chemicals, or outdoor elements. Combined with the Buna-N rubber O-ring, it effectively seals against fluids and gases up to 1500 psi, preventing leaks in hydraulic systems, pneumatic equipment, and pressurized enclosures. The Class 3A thread fit and coarse UNC threading ensure rapid assembly and vibration resistance, reducing downtime in automotive, aerospace, and manufacturing applications. Its fully threaded design offers uniform clamping force, while the hex drive facilitates access in confined spaces, enhancing operational efficiency and long-term performance.

Specification Summary & Compliance

This screw features precise Class 3A thread fit per UNC standards, with a thread size of 4-40 and length of 7/8". It complies with ASME B18.3, DIN 912, and ISO 4762 manufacturing specifications, ensuring dimensional accuracy and reliability. Additionally, it is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting environmental and safety regulations for industrial use.