S-95198A272 4-40 x 3/16" ASME B18.3, DIN 912, ISO 4762 Sealing Socket Head Screws

Key Features & Benefits at a Glance

• Superior sealing performance with integrated Buna-N rubber O-ring, preventing leaks in demanding applications up to 1500 psi
• Exceptional corrosion resistance provided by 18-8 stainless steel construction, ensuring long-term reliability in harsh environments
• Precise thread engagement with Class 3A thread fit, delivering secure fastening and vibration resistance in critical assemblies
• Wide temperature compatibility from -40° to 225°F, maintaining sealing integrity across extreme operating conditions
• High strength reliability with 100,000 psi tensile strength and Rockwell B85 hardness, preventing stripping and deformation under load
• Standardized socket head design with hex drive compatibility, enabling easy installation in confined spaces with common tools
• Full thread coverage along the 3/16" length, providing maximum grip and adjustment flexibility in assembly applications

Professional Applications & Engineering Value

This 4-40 UNC socket head cap screw delivers critical sealing solutions for industrial equipment, hydraulic systems, and precision machinery where fluid containment is paramount. The 18-8 stainless steel construction combined with the Buna-N rubber O-ring creates a reliable barrier against leaks, dust, and moisture ingress, addressing common failure points in pressurized systems. Engineered with Class 3A thread fit and coarse UNC threads, it ensures rapid assembly and secure fastening in high-vibration environments. The standard socket head profile with hex drive accommodates space-constrained applications while providing sufficient torque transmission. These fully threaded screws are particularly valuable in pump housings, valve assemblies, and industrial enclosures requiring both structural integrity and environmental sealing.

Specification Summary & Compliance

This socket head cap screw features precision 4-40 UNC coarse threads with Class 3A thread fit for superior dimensional accuracy. Manufactured to ASME B18.3, DIN 912, and ISO 4762 standards, ensuring interchangeability and quality consistency. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, meeting international safety and sustainability requirements for industrial components.