Bristle Discs are a molded, abrasive filled bristle disc which is used in automotive, industrial and DIY applications and can be used on aluminum, metal and wood. Use this product instead of a wire brush for many tasks including: deburring, blending, polishing, finishing, cleaning, coating and defect removal, scratch removal and rust removal. The product bristle disc is measured using its outside diameter which is 2 inches. It's quick change attachment makes it quick and easy to mount it to the tool or pad. The product rotates and spins, just like other products in its category, at the maximum speed possible. The bristle disc can run at a maximum speed of 25,000 RPM. WARNING: This product can expose you to chemicals which is [are] known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www. P65Warnings. ca. gov.