Features: Made of premium zirconia, high quality, long lasting and fast polishing, offer you extreme durability and value. Each disc measures at 115mm diameter with a 22mm arbor size, making it compatible with grinders operable of up to 12000 RPM. Can be used for grinding, deburring, rust removal, cleaning and finishing on both contoured and flat surfaces. Suitable for metals, wood, rust, paint, stainless steel and plastics. Not for concrete or stone. Two option for you, 60 grit or 80 grit, you can choose according to you demands.