1. Material: sandpaper 2. Scope of use: for jade, agate, jadeite, glaze, mold, electronics, glass, and other surface polishing 3. Suggestions: sandpaper stick please use low speed, recommended speed 2000-5000, please do not use super speed 4. Tip: 180 mesh sandpaper rod coarsest, polishing efficiency, the larger the number of mesh, the finer the polishing 5. Shank diameter: about 3mm 6. Weight: about 5g