DescriptionDiy crafts material: ceramic; shank diameter: 3mm/ 6mm; quantity: 10pcs per set it is a good assistant for grinding and polishing of metal and non-metal materials used for various kinds of electric grinder, grinding machine to remove burr, surface grinding, time - saving wide adaptability: it can play an excellent role especially for stainless steel and other metals. Low noise and few dust during grinding, and will not rust and fall out like the steel brush high hardness and toughness, durabale: the hardness of chrome corundum is similar to that of white corundum, and its toughness is higher, sharper and more durable