Features: ALL-IN-ONE KIT: This 25 piece thread repair tool kit includes bits, taps, and inserts in the 9 most needed metric sizes: M3,M4,M5, M6, M7 M8, M10,M12,M14 PURPOSE BUILT: The installation tools in this insert kit are constructed from high-speed steel for superior handling while the inserts are heated-treated steel for greater strength and longevity in place WIDE APPLICATION: Our drill and tap set is ideal for restoring stripped or damaged internal threads as well as for performing maintenance work to protect any threads from wear and tear EASY TO USE: Convenient cases hold and organize all the parts for easy transport and storage between jobs; on the site, the drill bits quickly create room for the installation tools to smoothly fit the inserts that repair your old threading.