Diamond bits are durable and cut sharp for glass, stone, ceramics, jade, jewelry, wood, plastic and other hard materials. Features: 30 Pieces Diamond Burrs SetExcellent for fine detail work, cutting, engraving, carving, touch-up and finishing Work on glass, metal , stone, ceramic, wood, plastic. FeatureVarious grinding head shape: ball, cylinder, cone, needle etc, meet your different carving or engraving need. Shank Diameter1 or 8andquot diameter shanks, compatible with most rotary tools Ideal for home improvement, craft and whenever you need to polish, grind, drill, cut, engrave, and more,used with most rotary tools. Long Working LifeThe working life of these solid rotary burr is 10 times longer than high-speed steel and 200 times longer than grinding wheel. Storage Box Plastic box is sturdy, falling resistant and moistureproof, easy for carrying and hanging. All parts were in order and set was complete, well organized to prevent scattered and confused. Specifications: Material: Metal Quantity: 30Pc Assortment Item Weight: 45 x 3mm or 1.77 x 0.12in Package Weight: 80g or 2.82oz Package Size: 14.5 x 6 x 2cm or 5.71 x 2.36 x 0.79in Package List: 30 x Diamond Burr Bits 1 x Storage Box