1Excellent Manganese Steel Material: This straight shank collet chuck holder is crafted from high-quality manganese steel, ensuring strength and durability, resistance to damage, and an extended service life. 2Quenched And Blackened Treatment: The surface of this collet chuck extension bar undergoes quenched and blackened treatment, providing excellent oxidation resistance, high hardness, and longevity. 3Straight Handle Design: This router collet chuck extension rod features a straight handle design, making it easy to operate while saving effort, effectively meeting your usage needs. 4Wide Application: This collet extension straight shank tool holder is versatile and suitable for use on CNC milling machines, serving as a perfect replacement for various parts. 5Multifunctional: This straight shank extension lathe rod is designed for use with ER16A collets to secure nuts, enhancing your work efficiency and durability in machining products.