S-91900A308 M5 x 40 mm ASTM F879M, ISO 7380 Tamper-Resistant Torx Stainless Steel Button Head Screws

Key Features & Benefits at a Glance

• Enhanced Security: Tamper-resistant T25 Torx drive prevents unauthorized removal, ideal for public or high-security installations.
• Superior Corrosion Resistance: 18-8 stainless steel with passivated finish ensures long-term durability in harsh environments, reducing maintenance costs.
• High Mechanical Strength: 80,000 psi tensile strength and Rockwell B96 hardness provide reliable performance under heavy loads and vibration.
• Precise Thread Fit: Class 6g thread fit and M5 x 0.8 mm coarse pitch enable quick, secure fastening with reduced cross-threading risk.
• Full Thread Engagement: Fully threaded 40 mm length offers maximum grip and uniform stress distribution in various material thicknesses.
• Rounded Head Design: Button-style rounded head minimizes snagging and provides a smooth, finished appearance.
• Global Compliance: Meets ASTM F879M and ISO 7380 standards, with RoHS 3 and REACH compliance for safe, international use.

Professional Applications & Engineering Value

These M5 metric screws are engineered to address critical fastening challenges in industrial and security-sensitive applications. The combination of 18-8 stainless steel and a passivated finish delivers exceptional resistance to corrosion, making them suitable for outdoor equipment, marine hardware, and chemical processing facilities where moisture and corrosive agents are prevalent. The tamper-resistant Torx drive (T25) ensures that fasteners remain securely in place, preventing vandalism or unauthorized access in public infrastructure, electrical enclosures, and transportation systems. With a fully threaded design and Class 6g thread fit, these screws provide consistent clamping force and reduce installation errors, enhancing assembly efficiency in automated production lines. Their high tensile strength (80,000 psi) and Rockwell B96 hardness guarantee reliable performance in high-stress environments, from machinery mounts to structural frameworks, ensuring long-term operational safety and reducing downtime.

Specification Summary & Compliance

This screw features precise metric threading (M5 x 0.8 mm) with a Class 6g thread fit per ISO standards, ensuring dimensional accuracy and compatibility with metric nuts and tapped holes. It is manufactured in accordance with ASTM F879M and ISO 7380 specifications, guaranteeing consistent quality and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of hazardous substances and supporting environmentally responsible procurement.