For fine detail work, cutting, engraving, carving, touch-up and finishing. Use on wood, jade, ceramic, glass, hardened steel, semi-precious stones and other hard materials. Bits are covered with diamond particles. Ideal for fine detail work on wood, jade, ceramic, glass, hardened steel and other hard materialsRemoves material quickly and easilyCovered with diamond particlesUse higher speeds for hard woods and slower speeds for metals1/8 in. shank