High Quality: The drill bit set is made of high quality tungsten steel, processing hardness up to HRA 85, perfect for iron, steel, carbon steel, alloy steel, stainless steel, copper, aluminum, etc. Multi-function: The carving drill bit set can be used for engraving, chamfering, grooving, reaming, hollowing, etc. The processing efficiency is ten times higher than that of the hand sanding tool and almost ten times higher than the small grinding wheel with the handle. Wide Application: The rotary grinding wheels can be used for engraving and milling soft wood, plastic and other soft materials, after carving, the surface will be smooth. Portable: The rotary grinding wheels come in a portable box, no need to keep order. Features: Material: Tungsten steel. Shank: 3 mm. Features: Assorted shapes and sizes: ball, cone, rounded cylinder, flat-top cylinder, tapered. 2. Cleaning the cup, veins and solder joints of casting, forging and welding. 3. Highly recommended for jewelers, lapidary use, hobbies, crafts, modeling, home repair, and much more. 4. Excellent for filing glass, ceramics, tile, brick, plastic, wood, fiberglass, stone, rock carbide, gold, platinum, silver, metals, and anything with a hard surface. 5. They are suitable for polishing metals and plastics. Can be used with most power tools. Widely Used: 1. Cleaning cutting, veins, and solder joints, forging, and welding. Finishing all kinds of metal molds. 2. Turbine passage of finishing processing. A variety of chamfered, round, and grooved mechanical parts. 4. Finishing the surface of the inner hole of machine parts. 5. Processing various metals and non-metallic carvings. Contents: 10 Tungsten Steel Rotary Burrs