General description 8 Pcs Cylinder Grinding Stone with a 1/4 inch hex shank, designed for use with rotary tools, drills, and die grinders. Made of durable alumina, these grinding stones are ideal for various applications including grinding, polishing, and sharpening of metals and non-metals. Technical specifications Material: Alumina Shank size: 6mm (1/4 inch) Cylinder diameter: 20mm Allowed measurement error: +/- 1-3cm Application Suitable for grinding aluminum, steel, alloys, and other metals Can be used for non-metal grinding and polishing Package Contents 8 x grinding stones Other information