1: Hook the headband into the nut first, then tighten it directly and hold it firmly.
2: Extension handle with straight shank, the handle body applies longer depth processing, eliminating the need for extending machining depth.
3: You can reduce the use of expansion tools, which can reduce costs and improve efficiency.
4: The diameter of the extension rod and other parts is precision ground, can eliminate the imbalance and increase safety when cutting.