S-98070A120 4-40 x 5/16" Sealing Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior Sealing Performance: Integrated silicone rubber O-ring ensures reliable sealing against fluids and gases, preventing leaks in critical applications.
• Exceptional Pressure & Temperature Resistance: Withstands up to 20,000 psi and temperatures from -150° to 500°F, ideal for demanding industrial environments.
• Corrosion-Resistant Durability: Made from 18-8 Stainless Steel with a passivated finish for enhanced resistance to rust and chemical degradation.
• Precision Thread Fit: Class 2A UNC coarse threads provide consistent, reliable engagement and ease of installation in various materials.
• Flush-Mount Design: Flat head with standard profile allows for a smooth, unobtrusive surface finish when installed.
• Broad Compliance & Safety: Compliant with RoHS 3 and REACH standards, ensuring environmental safety and regulatory acceptance.
• Versatile Drive Compatibility: Phillips No. 1 drive offers common tooling access for efficient assembly and maintenance.

Professional Applications & Engineering Value

This 4-40 UNC flat head Phillips screw is engineered to address critical sealing challenges in high-pressure and extreme temperature environments. Constructed from 18-8 Stainless Steel and featuring a fully threaded design with a silicone rubber O-ring, it effectively prevents leakage in applications such as hydraulic systems, pneumatic controls, and industrial machinery. The passivated finish enhances corrosion resistance, extending service life in harsh conditions, while the Class 2A thread fit ensures precise, secure fastening. Ideal for OEM and MRO uses, this screw provides a dependable sealing fastener solution that reduces downtime and maintenance costs in sectors like automotive, aerospace, and fluid handling systems.

Specification Summary & Compliance

This screw adheres to UNC coarse thread standards with a Class 2A thread fit for consistent dimensional accuracy. It is manufactured in accordance with industry specifications for flat head screws, including a countersink angle of 100°. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, it meets stringent environmental and safety requirements for global use.