Check the listing for details. 20Pcs Diamond Grinding Bit 5mm 3/16" Spherical Circular Ball Head Lapidary Tools. Color: Silver, Condition: New. Listed at 14.99 USD. 20Pcs Diamond Grinding Bits 5mm 3/16" Spherical Head with 2.35mm Shank Code 50F*2.35mm Specification: Product Name Diamond grinding bits Tip Shape Spherical/ Round ball Material Steel, Diamond Head Diameter 5mm (Close to 3/16") Shank Diameter 2.35mm (Close to 3/32") Total Length 45mm ( 1-3/4") Grit 120 (Medium) Color Silver Tone Quantity 20Pcs Description:Round ball shape, diamond coated grinding headThe speed of 5000-35000 r/min,electric grinder speed as high as possible.Shank Diameter: 2.35mm(3/32"); Suitable for electric nail drill, carving machine with a 3/32" colletThe grinding bits can be installed on the electric grinder, hanging mill and hand electric drill (not included here). Never use drills while machine is in hammer action.Product use: apply to stone carving, jade carving, bone carving, egg decorating, glass carving etc.Used for sculpturing, dressing, precision grinding and internal grinding carbide in ceramic, glass, precious stone, alloy and many the abrasive materialsUse with water as a lubricantNote: carving must use cold water to cool the workpiece and the grinding head polishing, moment also can't do without waterWe can list any size & amount of this product: Head diameter from 1 mm to 40 mm Regular Air postage from China to Worldwide and takes 15-30 days delivery to your homeWe will send out your order within 1-2 days after payment has been received and cleared. Just a friendly reminder: The Shank diameter of grinding bit is 2.35mm (3/32" inch)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