Check the listing for details. 30Pcs 2mm Diamond Grinding Bits Cylindrical Bur Lapidary Carving Tools for Stone. Color: Silver, Condition: New. Listed at 14.99 USD. 30Pcs 2mm Diamond Coated Grinding Bits for Jewelry Gemstone Glass Tile Marble Granite Code 20A The diamond coated grinding bit is suitable for use in grinding process on jewelry, gems, glass, marble, tile or granite Product Specification: Product Name: Lapidary Diamond Grinding Bits, Diamond Carving Tools for Stone Head Diameter: 2mm Total length: 1-21/32"(42mm) Head length: 1/4" (6mm ) Shank diameter: 3/32" (2.35mm) Suitable for electric nail drill, carving machine, machinery supporting assembly with a 3/32" collet Quantity: 30 Pcs Use with water as a lubricant Diamond grinding head is ideal tools for grinding mold, hard alloy, glass apparatus, jade carvings Usage: used for mould grinding, grinding inner hole, suitable for electric grinder, carving machine, electric machinery supporting assembly, mainly used for carving glass, jade, fixed abrasive and hard objects We Can List Any Size (Head Diameter from 0.4mm - 230mm) & Amount of This Product We will send out your order within 1-2 days after payment has been received and cleared. Please let us know if you are looking for other accessories or hardware. Just a friendly reminder: The Shank diameter of grinding bit is 2.35mm (close to 3/32")There are two different collet sizes for Dremel: 3mm (1/8") or Universal 3-jaw chuckIf your chuck of Dremel (models 4300-8050) has an Universal 3-jaw chuck, then the grinding bit can be installed directlyHowever, it is NOT suitable for dremel with 3mm 1/8" chuck (such as:models 3000,4000)If your chuck of Dremel is 3mm (1/8"), maybe you need add the Universal 3-jaw chuck for Dremel