The Hertel Extension Tap is a precision threading tool designed for creating M4 x 0.7 metric coarse threads. Featuring 2 flutes and a D4 design, this high-quality tap is crafted from durable High Speed Steel with a spiral point (plug chamfer) configuration that efficiently channels chips forward—ideal for through holes. With a generous 6-inch overall length, this extension tap provides excellent reach for deep threading applications while maintaining stability and control. The 6H class of fit ensures industry-standard thread precision and compatibility. This professional-grade threading tool is manufactured by MSC Industrial under the trusted Hertel brand (Part #G859441). Perfect for machinists, toolmakers, and manufacturing professionals who demand reliable performance when creating metric threads in hard-to-reach areas.