S-93401A100 4-40 x 1/4" ASTM F835, MS24667-1 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance thanks to cadmium plating, extending service life in harsh industrial environments
• Exceptional tensile strength of 140,000 psi prevents stripping and failure under high-stress conditions
• Precise Class 3A thread fit ensures reliable, vibration-resistant connections in critical assemblies
• 82° countersink angle provides a flush, professional finish that eliminates protrusions
• Hex drive design allows for high-torque installation with standard tools, reducing assembly time
• Rockwell C39 hardness maintains thread integrity and resists wear during repeated use
• Full threading along the 1/4" length offers maximum grip and adjustment flexibility

Professional Applications & Engineering Value

These 4-40 UNC flat head screws are engineered for demanding applications where precision and durability are non-negotiable. Constructed from cadmium-plated alloy steel, they provide excellent corrosion resistance, making them ideal for electronics, aerospace components, and machinery exposed to moisture or chemicals. The Class 3A thread fit and coarse UNC threading ensure secure fastening that resists loosening from vibrations, while the 82° countersink allows for seamless integration into surfaces. With a hex drive for easy installation and full threading for maximum holding power, these screws solve common issues of fastener failure and misalignment in industrial assembly lines and precision equipment.

Specification Summary & Compliance

This product adheres to strict dimensional tolerances, including a Class 3A thread fit for precision and UNC coarse thread spacing. It complies with ASTM F835 under specification MS24667-1, ensuring consistent quality and performance. The screw features a right-hand thread direction, fully threaded design, and meets industry standards for material and manufacturing integrity.