The Hertel Extension Tap is a precision threading tool designed for creating internal threads in deep holes or recessed areas. This 1/4-20 UNC tap features 4 flutes for efficient chip evacuation and a bright/uncoated finish for excellent visibility during operation. Crafted from high-quality High Speed Steel (HSS), it offers superior durability and cutting performance even in challenging materials. The H3 spiral point design helps push chips forward, making it ideal for through holes. With a generous 6" overall length, this extension tap reaches areas standard taps cannot access. The plug chamfer provides a standard thread entry, while the 3B class of fit ensures precise threading to specification. This professional-grade tap is manufactured by MSC Industrial under the trusted Hertel brand (Part #G837581), making it a reliable choice for machinists, maintenance professionals, and manufacturing operations requiring consistent threading results.