S-93401A102 4-40 x 3/8" ASTM F835, MS24667-2 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with cadmium plating, extending service life in harsh industrial environments
• Exceptional tensile strength of 140,000 psi for reliable performance under heavy loads and vibration
• Precise Class 3A thread fit ensures secure fastening with minimal risk of loosening or cross-threading
• Optimized 82° countersink angle provides flush mounting for streamlined assemblies and improved aesthetics
• Enhanced installation control with hex drive design, allowing high torque application without slippage
• High hardness rating (Rockwell C39) resists wear and deformation during repeated use
• Full threading along the 3/8" length maximizes grip strength and load distribution

Professional Applications & Engineering Value

These 4-40 UNC flat head screws deliver critical reliability in demanding applications where vibration resistance and precise alignment are paramount. Manufactured from cadmium-plated alloy steel, they combat corrosion in machinery, electrical enclosures, and automotive assemblies. The coarse UNC thread and Class 3A fit prevent stripping in softer materials, while the 82° countersink ensures a seamless finish. With 140,000 psi tensile strength and hex drive compatibility, they withstand extreme mechanical stress and enable efficient installation in confined spaces, reducing assembly time and maintenance costs.

Specification Summary & Compliance

This screw features Class 3A thread fit per UNC standards with a coarse thread spacing, ensuring dimensional accuracy and interchangeability. It complies with ASTM F835 MS24667-2 specifications, guaranteeing consistent quality and performance. The cadmium plating meets RoHS and REACH environmental guidelines, while the inch system measurements provide compatibility with North American machinery and equipment standards.