Package Include: This set includes 50 pieces of diamond coated rotary burrs, featuring a variety of head styles and small head designs for accurate work. Widely Used: They are versatile tools suitable for use on various materials including stone, ceramics, glass, hard alloys, and precious gemstones. Grinding Burrs: Primarily, these grinding heads are ideal for engraving glass, gemstones, stones, and other hard objects providing professional results every time. Product Features: These diamond grinding heads offer high sharpness and minimal cutting gaps for efficient and smooth operations. Good Accessories: They can be used for grinding or cutting the surface of objects as well as sharpening tools, making them a widely applicable addition to any toolkit. Specification: Material: Electroplated Emery Shank Diameter: 0.31cm/0.12inch Package Includes: 50pcs/Box Grinding Stones Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful online shopping!