This soft natural rubber Expander Wheel conforms to slightly contoured pieces and leaves a smooth, uniform finish. Can be used with abrasive bands, Scotch- Brite belts or the Trizact belts. They stay firmly in place because centrif- ugal force expands the rubber wheel. The Expander Wheel is designed to run at 1,800 rpm so excessive cutting does not occur. DO NOT OPERATE FASTER THAN 2400 RPM!!!!!!!!