Various Shapes: The diamond drill bit set for rotary tools contains 20 pieces in total, designed in different shapes, such as spherical, pointed cone, cylindrical, oval, bullet, flat rectangle, etc. Different models and different shapes. Will meet your different needs. No matter what shape you need to carve or polish, our diamond drill bit sets are here for you.Multifunctional: Diamond drill bits are ideal for home decoration and crafts, and are a good helper for grinding, sanding, drilling, cutting, engraving, etc. Capable of engraving on a variety of materials, including: tiles, ceramics, marble, granite and other hard materials. In interior decoration or crafts, diamond drill bits are indispensable tools. It can engrave a variety of hard materials and demonstrate exquisite craftsmanship.Material: Diamond drill bits are made of reliable quality diamond particles, thick and durable, wear-resistant, high hardness and impact resistance, durable enough for fine detail work. In