Applications: Use with electric mini routers/routers and flexible shafts. [Features/Functions] Diamond bits are used for a variety of grinding processes, such as carbide and precision processing of glass products and accessories, and the finish of the molds, removing rust from metal deburring, finding drills, scissors, and other grinding, such as molds, removing rust and precious metal processing, crafting, grooving, and welding finishing. Compatible models can be used with mini routers and electric drills from any manufacturer that supports 0.09 inch (2.35 mm) axis. Maximum Diamond Bits Supported Rotation Speed: 40,000 (rpm); Maximum Compatible Whetstone with Axis: 20,000 rpm (rpm); Caution: When working, please make sure to use safety equipment such as safety glasses and other safety equipment to ensure that your hands and face are close to rotating objects. Do not use for anything other than the intended purpose. Please check if there are any abnormalities such as deformation, breakage, or curving. Close to the zipper as possible and tighten tightly to eliminate wick shaking. If the installation is loose, it is very dangerous to slip during rotation. When attaching the bits to a mini router, please ensure that the shaft protrusion (overhang) or less is 0.5 inches (13 mm). Please carefully read the manufacturers instructions for the mini router or router you are using and observe the warnings and warnings from each manufacturer. Do not use near children. Keep out of reach of small children.