S-90517A240 M4 x 16 mm ASTM F879M Tamper-Resistant Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Enhanced tamper resistance with specialized hex drive requiring matching tools, preventing unauthorized access in secure installations
• Superior corrosion resistance through 18-8 stainless steel construction and passivated surface treatment for extended service life in harsh environments
• High mechanical strength with 80,000 PSI tensile strength and Rockwell B96 hardness to withstand substantial loads and vibration
• Precision thread engagement with Class 6g tolerance and coarse M4x0.7mm threading for reliable fastening in various materials
• Streamlined installation featuring standard 90° flat head profile that sits flush with surfaces for clean, professional finishes
• Full regulatory compliance meeting ASTM F879M, RoHS 3, and REACH standards for quality assurance and environmental safety
• Complete thread coverage along the 16mm length ensures maximum grip strength and distribution of clamping forces

Professional Applications & Engineering Value

This M4 metric flat head screw delivers critical security and durability for industrial applications where tampering prevention and environmental resistance are paramount. The 18-8 stainless steel construction combined with passivated finish creates a robust barrier against corrosion, chemicals, and moisture exposure in manufacturing facilities, outdoor equipment, and electronic enclosures. The tamper-resistant hex drive system provides an essential security layer for public infrastructure, transportation systems, and access panels while maintaining the installation efficiency of standard hex drives. With fully threaded M4x0.7mm coarse threading and Class 6g precision, these screws offer reliable engagement in metals, plastics, and composite materials, reducing installation time and ensuring consistent clamping force across demanding assembly operations.

Specification Summary & Compliance

This security fastener features M4x0.7mm coarse threading with Class 6g thread fit tolerance, 16mm fully threaded length, and 90° countersink angle. Manufacturing and quality control adhere to ASTM F879M specification requirements. The product maintains full compliance with RoHS 3 (2015/863/EU) restrictions on hazardous substances and REACH (EC 1907/2006) regulations concerning chemical substances, ensuring environmental responsibility and workplace safety standards are met for global industrial applications.