Paper abrasive specific safety, silentness, work efficiency and durability to its maximum, a product without price difference with conventional whetstone.Made in Japan paper is used.High hardness material principally composed of alumina oxide.Steel grinding/polishing, welding bead scraping, rust remover, paint removal, wood polishing.Grain Size (#):120Outer Diameter x Blade Length x Hole Diameter (mm):100 x 15 x 15Max Working Rotation Speed (rpm):13600Blade Number (sheet):72Grinding Angle: 15 to 30Max Working Peripheral Velocity: 72m/s (4300m/min)