1、MAIN FUNCTION: The extension rod can bring the milling cutter into the deep hole processing slot for processing, solve the deep hole processing problem for you. 2、HIGH HARDNESS: CNC milling extension rod is forged from high hardness carbide, quenched and hardened, hard to deform. 3、FINE MADE: The inner hole of the extension rod is finely ground, with high concentricity, smoothly thread, high rigidity, strong clamping force. 4、IMPROVE EFFICIENCY: This CNC extension shank can be used for powerful milling to improve efficiency, which is convenient to install and removal. 5、WIDE USAGE: The extension rod is widely used in CNC lathes, machining centers, tapping machines, drilling machines, milling machines and other equipment.