The Wiseman Threading Tools Second Lead Metric HSS Tap Left Hand - M12x1.25 is a purpose-built solution for precision left-hand threading in metalworking projects. Forged from high-speed steel and ground to exact specifications, this uncoated tap delivers dependable, clean threads that stand up to repeated use in a range of metals. Designed to ISO 529 standards, it ensures consistent pitch and fit across parts that require reverse-threaded fasteners.

Why this tap stands out

• Left-hand, metric threading: M12x1.25 left-hand thread for reverse-torque applications and anti-rotation assemblies.
• Second lead design: Optimized for faster cutting and efficient chip evacuation, helping you complete through-holes more quickly without sacrificing thread quality.
• High-speed steel, ground finish: Precision-ground cutting edges with durable HSS material provide reliable performance in steel, aluminum, and other common metals.
• ISO 529 compliant: Dimensionally accurate and compatible with standard metric taps and nut/bolt systems, reducing fit issues in production work.
• Uncoated versatility: The uncoated surface accepts a wide range of cutting oils and coolants, letting you tailor lubrication to your material and workflow.
• USA plug lead configuration: Built for compatibility with common tapping setups used in the United States, ensuring smooth integration into your shop tooling.

Practical applications: This tap shines in reverse-thread assemblies, retrofit work where components rely on a left-hand fastener, and fabrication tasks that require rapid, repeatable thread formation. Whether you’re repairing a fixture, preparing a mounting plate, or manufacturing small-alternate-threaded components, this tool delivers dependable results with predictable outcomes you can trust project after project.

Usage tips for best results: Use a suitable tap handle and steady, moderate pressure with a quality cutting fluid. Start the thread slowly to establish alignment, maintain a consistent spinning motion, and back off occasionally to break chips. For best longevity, avoid pushing beyond the recommended depth and monitor heat buildup during deeper holes.