The Carmex Thread Mills Carbide Mini Type, No. 4 x 40, MT7, is a high-precision thread milling tool designed for UNC/UNF/UNEF/UNS threads. Built for machinists who need reliable internal and external threads in deep holes with a single, versatile tool.

• Tool material: Carbide MT7 sub-micron grade with a TiAlN multi-layer coating (ISO K10–K20) for outstanding wear resistance and heat tolerance.
• Threading capability: Produces both internal and external threads across UNC, UNF, UNEF, and UNS forms using one tool.
• No. 4 x 40 size: Precisely matched to No. 4 x 40 thread dimensions for broad, practical applicability.
• Deep-hole performance: Through-flutes and coolant delivery enable effective cooling and chip evacuation in deep-hole work.
• Spiral flute geometry: Smooth cutting action and enhanced chip control for cleaner threads and longer tool life.
• Multi-flute design: 3–5 flutes shorten machining time while maintaining rigidity and precision.
• Short profile: Reduces cutting forces and improves stability during high-speed threading operations.
• Material hardness compatibility: Capable of machining hardened materials up to 45 HRC, expanding its versatile use.
• Durability: Triple-coated surface enhances life and consistent performance across multiple jobs.

With this tool, you gain a single, durable solution for threading holes and bosses across a range of pitches, all without changing tools. Its through-coolant design supports high-speed threading in deep holes, while the short profile and multi-flute geometry deliver faster cycle times and stable cuts. Ideal for demanding applications in aerospace, automotive, and general manufacturing, this thread mill reduces downtime, minimizes tool changes, and delivers precise, repeatable threads in hardened metals up to 45 HRC.