S-98070A178 1/4"-20 x 1/2" Sealing Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel and passivated finish, ensuring long-term reliability in harsh environments.
• Reliable high-pressure sealing up to 1500 psi with the integrated Buna-N rubber O-ring, preventing leaks in critical applications.
• Wide temperature tolerance from -40° to 225°F, maintaining performance in extreme thermal conditions.
• High tensile strength of 70,000 psi for secure fastening under demanding mechanical loads.
• Precise Class 2A thread fit with UNC coarse threading, enabling quick installation and reduced cross-threading risks.
• Undercut flat head design for a flush, low-profile finish that minimizes protrusion and improves aesthetics.
• Compliance with RoHS 3 and REACH regulations, ensuring environmental safety and global market suitability.

Professional Applications & Engineering Value

This 1/4"-20 UNC flat head Phillips screw is engineered to address common industrial sealing challenges, such as fluid leakage and corrosion-induced failure. The combination of 18-8 stainless steel and a passivated finish provides exceptional resistance to rust and chemical exposure, ideal for outdoor or humid settings. The integrated Buna-N rubber O-ring creates a dependable seal in hydraulic systems, pneumatic equipment, and machinery enclosures, withstanding pressures up to 1500 psi. Its undercut flat head profile ensures a smooth surface finish, reducing snagging risks in assembly lines. These features make it a top choice for OEMs and maintenance teams in automotive, marine, and industrial manufacturing, where durability and leak-proof performance are critical.

Specification Summary & Compliance

The screw features a 1/4"-20 UNC coarse thread with Class 2A thread fit for standard dimensional accuracy and easy assembly. It is fully threaded for consistent grip and includes a Phillips No. 3 drive for efficient torque application. Manufacturing adheres to industry standards, and the product is verified as RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting strict environmental and safety regulations for global industrial use.