Pearl Abrasive 4-1/2 x 7/8 AO Maroon Surface Preparation Wheel, Fine Grit - Box of 10THIS ITEM IS A BOX OF 10 WHEELS For surface preparation. Aluminum Oxide. For ferrous metals, iron, steel, non ferrous metals, sheet metals, copper and stainless steel. Max RPM: 13,300. T 27 shape. WARNING: This product can expose you to chemicals, including Phenol, Formaldehyde, and Sulfur, which are known to the State of California to cause cancer or birth defects or other reproductive harm. For more information, go to