Product description Size:? 25mm Suitable for most rotary tools,including ; Hand Drill Cutting Discs diameter: 25mm; Mandrel Diameter:3.0mm Higher quality material, designed for Rotary Tools, diamond coated for extra strength and long life of blades Widely uses, small kerf, sharpness. These cutting discs are perfect for cutting and polishing glass, tiles, marble, plastic, jade, agate, crystal and other products Warm Tips: For your safety, please must wear gloves and goggles and be care around spark when using cutting tools. It may become very hot when cutting, add some water to keep it cool