... advanced Italian technologies. 2. Using best abrasives, fillers, resin 3. Flat center cutting wheel/depressed center cutting wheel4. Note: Arbor hole ... . Color: Black, Brown.6. Product diameter: 4", 4-1 / 2", 5", 6", 7", 9", 12", 14", 16". (100mm to 400mm)Benefits ... steel, Stone Cutting 3. Fast Cutting 4. very long life 5. easy to use Cutting & Grinding Wheel