S-91518A190 M8 x 16 mm Left-Hand-Thread Stainless Steel Hex-Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 18-8 stainless steel construction and passivated finish, ensuring long-term durability in harsh environments.
• Reliable left-hand threading for specialized applications where reverse-direction fastening prevents loosening under counter-clockwise rotation.
• High tensile strength of 70,000 psi and Rockwell B70 hardness for secure, vibration-resistant connections in demanding industrial settings.
• Secure installation with a 5mm hex drive, providing positive torque control and reducing the risk of stripping during assembly.
• Precise Class 6g thread fit and coarse 1.25mm pitch for quick engagement and consistent performance in metric assemblies.
• 90° countersink angle and flat head design for a flush, low-profile finish that enhances safety and aesthetics.
• Full compliance with RoHS 3 and REACH regulations, ensuring environmental safety and global supply chain acceptance.

Professional Applications & Engineering Value

This M8 left hand flat head screw is engineered to address critical challenges in machinery, automotive, and equipment manufacturing where standard right-hand threads may loosen under specific rotational forces. The 18-8 stainless steel material combined with a passivated finish provides superior resistance to rust and chemical exposure, making it ideal for outdoor, marine, or high-moisture environments. The left-hand metric thread with coarse 1.25mm pitch ensures rapid assembly and disassembly in maintenance-heavy applications, while the hex drive offers reliable torque transmission without cam-out. Fully threaded for maximum grip length, it delivers consistent clamping force in industrial fastening scenarios, reducing downtime and enhancing operational safety.

Specification Summary & Compliance

This screw features M8 x 1.25mm left-hand metric coarse threads with a Class 6g tolerance for precise fit. Dimensions include a 16mm length, 16mm head diameter, and 4.4mm head height. It is manufactured from 18-8 stainless steel with a passivated finish, achieving 70,000 psi tensile strength and Rockwell B70 hardness. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) standards, ensuring adherence to environmental and safety regulations.