S-96640A334 4-40 x 1/4" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with Black-Oxide coated 18-8 Stainless Steel, ideal for harsh industrial environments
• Superior tensile strength of 80,000 psi ensures reliable performance under high-stress applications
• Rockwell B80 hardness provides excellent durability and resistance to wear over time
• 100° countersink angle and flat head design allows for flush mounting, reducing snagging and improving safety
• Class 2A thread fit with coarse UNC threading enables quick, secure installation and easy disassembly
• Fully threaded shank maximizes grip and holding power across the entire length
• Phillips No. 1 drive offers common tool compatibility for efficient assembly processes

Professional Applications & Engineering Value

These 4-40 UNC flat head Phillips machine screws are engineered to address critical industrial fastening challenges. The Black-Oxide 18-8 Stainless Steel construction provides superior corrosion resistance, making them ideal for applications in moist or chemically aggressive environments like electronics enclosures, automotive assemblies, and machinery panels. The fully threaded coarse UNC design ensures rapid installation and high vibration resistance, reducing maintenance downtime. With a 100° countersink angle, they sit flush with surfaces, preventing interference in tight spaces. This combination of material durability, precise threading, and compliant design delivers long-term reliability for OEM and MRO professionals seeking consistent performance.

Specification Summary & Compliance

This screw features a 1/4" length with Class 2A thread fit and coarse 4-40 UNC threading for precise dimensional accuracy. It is manufactured in compliance with ASME B18.6.3 standards for consistent quality and performance. The product is fully RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliant, ensuring environmental safety and regulatory adherence for global industrial use.