S-90825A841 1/4"-28 x 1/2" Sealing Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Superior Sealing Performance: Integrated Buna-N rubber O-ring creates a reliable seal against fluids and gases, withstanding pressures up to 6000 psi for leak-free operation in demanding environments.
• Exceptional Corrosion Resistance: Constructed from 18-8 Stainless Steel with a passivated finish, offering excellent protection against rust and chemical degradation, extending service life.
• Wide Temperature Tolerance: O-ring maintains sealing integrity across a broad temperature range from -30° to 250° F, ensuring performance stability in varying thermal conditions.
• High Tensile Strength: With a tensile strength of 70,000 psi, this screw provides robust clamping force and structural reliability for heavy-duty assemblies.
• Precision Thread Fit: Class 2A UNF fine threads ensure smooth engagement, reduced cross-threading risk, and consistent fastening in precision-machined components.
• Efficient Installation: Phillips No. 3 drive and rounded pan head design allow for quick, secure tool engagement and a low-profile finish that minimizes snagging.
• Regulatory Compliance: Meets RoHS 3 and REACH environmental standards, ensuring safe use in regulated industries without hazardous substances.

Professional Applications & Engineering Value

This 1/4"-28 UNF Rounded Head Phillips Screw is engineered to address critical sealing challenges in industrial and fluid handling systems. The combination of 18-8 Stainless Steel and a passivated finish provides outstanding corrosion resistance, ideal for harsh environments like chemical processing, marine, or outdoor equipment. The Buna-N rubber O-ring ensures a tight seal against high-pressure fluids (up to 6000 psi), preventing leaks in hydraulic systems, pumps, and compressed air applications. Its fully threaded design and Class 2A thread fit guarantee uniform stress distribution and secure fastening in assemblies requiring fine adjustment. Commonly used in machinery, automotive, and aerospace sectors, this sealing fastener reduces maintenance downtime and enhances system reliability by eliminating common failure points associated with vibration and thermal cycling.

Specification Summary & Compliance

This fastener features a 1/4"-28 UNF fine thread with Class 2A fit for precise tolerance, a rounded pan head with Phillips No. 3 drive, and a length of 1/2". It is manufactured from 18-8 Stainless Steel with a passivated surface treatment and includes a Buna-N O-ring rated for temperatures from -30° to 250° F. The product complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring adherence to international environmental and safety standards for industrial components.