[PREMIUM CARBIDE BURRS SET]: This set includes 8 of the most popular shapes in a fitted case. With 1/4 inch shank, suitable for the process of various metals and most rotary grinders. Great choice for precise metal removal when shaping, leveling or porting cast iron, steel and other ferrous metals. [ADVANCES TUNSTEN MATERIAL]: 100% raw virgin tungsten carbide burrs which has a very long service life, 10 times the durability of other HSS burrs and 200 times the durability of small wheel. The hardness can reach HRC70, sharp and sturdy. [DOUBLE CUTTING PRECISE]: Double cutting style, right and left helical flutes combine to produce a chisel-like cutting tooth, this precision, when combined with precision grinders, results in smooth operation, fast metal removal and fine finishes. [WIDELY APPLICATION]: Widely used for metalworking, tool making, model engineering, wood carving, jewelry making, welding, chamfering, casting, deburring, grinding, cylinder head porting and sculpting. Include