1[High Hardness] Our collet chuck holder is made from premium manganese steel, featuring a surface quenching and blacking treatment, offering excellent oxidation resistance, high hardness, and a long lifespan. 2[Strong Clamping Force] With a clamping range of 1 to 10mm, this milling chuck holder provides a strong clamping force, ensuring secure and reliable tool gripping. 3[Convenient Tool Change] Equipped with an ER16A wrench, our milling tool holder allows for easy and quick tool changes. Also comes with a storage box for convenient storage and carrying. 4[Wide Application] Suitable for use with drilling machines, milling machines, lathes, bench drills, and small machine tools, this collet chuck holder is a versatile tool holder for various machining applications. 5[Long Lasting] Crafted with precise and built to last, our MTB3 ER16 (M12) collet chuck holder offers both performance and durability, making it an essential tool for machining tasks.