General description 90 PCS Diamond Burrs are excellent for fine detail work, cutting, engraving, carving, touching up, and finishing. They are suitable for use on glass, metal, stone, ceramics, wood, and plastic. With 30 different styles, these router bits can achieve more intricate carvings, making them ideal for jewelry design and various crafts, including necklaces, earrings, pendants, bracelets, and more. Technical specifications Quantity: 90 pcs Shank diameter: 1/8 inch (3 mm) Total length: 1.77 inches Material: Alloy Usage Ideal for wet drilling only; do not run dry. Start the hole at an angle for better results. While drilling, carefully move the tool to scroll the sides of the hole. Let the tool do the work without applying excessive pressure. Other information Package includes: 90 pcs in a plastic box for easy storage and transport.