1Excellent Manganese Steel Material: This straight shank collet chuck holder is made of excellent manganese steel material, which is strong and durable, not easy to be damaged, and has a long service life. 2Quenched And Blackened Treatment: The surface of this collet chuck extension bar is quenched and blackened, with strong anti oxidation ability, high hardness and long service life. 3Straight Handle Design: This router collet chuck extension rod is designed with a straight handle, which is very easy to operate and saves your effort, and it can meet your usage needs. 4Wide Application: This collet extension straight shank tool holder has a wide range of applications and can be used on CNC milling machines, perfect replacement for parts. 5Multifunctional: This straight shank extension lathe rod is used for ER16A collets to clamp nuts, making your work better, more efficient and more durable for machining products.