1 Material: Rotary file is made of heat treated tungsten carbide material, high hardness, wear resistant and sturdy. 2Good Work Efficiency: Using these rotary burr set with a rotary tool, the processing efficiency is higher than the manual file tool, convenient for using. 3Eco Friendly: Rotary burr set can take place of the small grinding wheel with the handle, producing less dust or pollution, more eco friendly. 4Durable: Durability is ten times higher than high?speed steel tools and more than 200 times higher than the small grinding wheels, safe and reliable. 5Widely Use: Carbide burr set is widely used in industrial sectors such as machinery, aviation, automobile, shipbuilding, chemical engineering and process engraving.