The Wiseman Threading Tools Second Lead Metric HSS Tap Left Hand - M16x2 is a precision-built hand tap designed to cut left-hand internal threads with reliability and control. Crafted from high-speed steel, this tool is ground for a clean, accurate thread form and is uncoated for versatile use across a variety of materials. Its ISO 529-compliant dimensions ensure compatibility with standard metric taps, so it fits seamlessly into your existing threading toolkit.

Key advantages that matter in real-world tapping

• Left-hand thread, M16x2: Specifically sized for metric left-handed threads, this tap enables reliable threading in applications where reverse-threaded fasteners are required.
• Second lead (plug/second tap design): The double-start geometry speeds up the cutting process, reducing the number of turns needed and improving productivity when working through tough or longer holes.
• High-speed steel, ground finish, uncoated: A ground fluted profile delivers smoother chip evacuation and consistent thread quality, while the uncoated surface handles standard cutting oils without the need for coatings. Ideal for general-purpose tapping in steel, aluminum, brass, and similar metals.
• ISO 529 compliant: Rely on established industry standards for predictable thread form and compatibility with other ISO 529-based taps and taps sets.

How to get the best results

Prepare the hole with the correct pilot diameter for M16x2 left-hand threads and use a compatible cutting fluid or oil to reduce heat and chip buildup. Align the tap carefully to ensure straight cutting, then rotate counterclockwise to create the left-hand threads. When the chips start to pack, reverse slightly to break the chips and continue. The second-lead design helps you progress smoothly, but maintain steady, even pressure to preserve thread integrity and tool life. Refer to ISO 529 guidelines for optimal feed and depth, and always back off briefly to clear chips after a few turns.

Ideal uses and who benefits

• Repair and maintenance tasks in equipment that employs left-handed fasteners or anti-assembly features.
• Hobbyists and professional machinists working in metalworking shops, automotive, or aerospace-grade assemblies where precision metric threads are required.
• Projects involving mild steel, aluminum, brass, or other common metals, especially when a controlled left-hand thread is needed for reliability under vibration or reverse-loading conditions.

Why choose Wiseman for threading tools

Wiseman Threading Tools are recognized for their precision-ground taps, adherence to ISO standards, and broad range of metric options. The second-lead, left-hand M16x2 taps are designed to deliver repeatable thread forms in serviceable, general-purpose applications. This combination of reliability, throughput, and compatibility makes it a practical choice for professionals who expect consistent results from their hand tapping work.