1. Steel is preferred for durability. Selected high-quality 65Mn, after high-frequency heat treatment and cryogenic treatment, has high strength and fatigue limit, stable performance and large clamping force. 2. Internal and external grinding, the accuracy is guaranteed. The surface is ground and polished, with a bright appearance and good fit.1. Fit the slot of the spring collet into the eccentric circle position of the nut, and push the spring collet in the direction indicated by the arrow until a click is heard, indicating that the spring collet is in place. 2. Install the collet on the tool, making sure it is in place. 3. Install the nut on the handle and tighten it with a wrench.After unscrewing the nut from the handle, pull out the tool, push inward from the front of the collet and press down against the bottom of the eccentric circle at the same time, and push the collet diagonally until the collet and the nut disassemble open.