Size: Total length: 54-68mm, Handle: 6mm, Drill diameter: 8mm, Drill length: 11-28mm, fits most small rotary tools. High quality: Double rotary burrs made of high-strength processed tungsten carbide, high abrasion resistance and good toughness. The processing hardness reaches up to HRC85, packed in a plastic case for safe storage and protection. High efficiency: The rotary burr set has high production efficiency, nearly 10 times higher than the small grinding wheel with handle. In most cases, it can replace a small grinding wheel without dust contamination. Design: Beveled, rounded and grooved mechanical parts. Double slot with cross lines, not easy to block the lines, more suitable for the relatively low density object material. Wide use: suitable for metal polishing, wood carving, jewelry, hobbies, crafts, craft styling, home repair, etc. Note: The data are all manually measured, please allow 1-3cm error, due to different light and display, there may be some color differences,