S-93802A438 4-40 x 3/4" MIL-DTL-18240, MS3212-8L, NASM3212, NASM82496 Sealing Thread-Locking Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Superior sealing performance with silicone O-ring and nylon patch thread locker, maintaining integrity from -40° to 400° F and up to 6000 psi pressure.
• Exceptional corrosion resistance thanks to 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments.
• Reliable vibration resistance through the nylon patch locking feature, preventing loosening in dynamic applications.
• Broad compatibility and easy installation with standard Phillips No. 1 drive and UNC coarse threads, ensuring quick assembly and disassembly.
• High tensile strength of 70,000 psi for durable, long-lasting fastening in demanding mechanical setups.
• Precise thread fit (Class 2A) and fully threaded design, providing consistent engagement and reduced risk of cross-threading.
• Compliance with major industry standards including MIL-DTL-18240, ensuring quality and reliability for critical applications.

Professional Applications & Engineering Value

This 4-40 UNC coarse thread screw with a rounded pan head is engineered to address common industrial challenges such as fluid leakage and vibration-induced failure. The combination of a silicone rubber O-ring and nylon patch thread locker creates a dual-sealing mechanism that withstands extreme temperatures from -40° to 400° F and pressures up to 6000 psi, making it ideal for hydraulic systems, aerospace components, and automotive assemblies. Made from 18-8 stainless steel with a passivated finish, it offers excellent resistance to corrosion and wear, while the Phillips drive ensures efficient installation in tight spaces. This screw is perfect for applications requiring reliable sealing and locking performance without compromising on durability or compliance with stringent military and environmental standards.

Specification Summary & Compliance

The screw features a Class 2A thread fit with UNC coarse threading and a length of 3/4", ensuring precise dimensional accuracy per industry norms. It meets specifications under MIL-DTL-18240, MS3212-8L, NASM3212, and NASM82496, and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, guaranteeing safety and environmental responsibility in manufacturing and use.