The Mercer 397MRN is a 7 x 7/8-Inch Aluminum Oxide Prep Wheel. This is made from non-woven synthetic fiber with adhesive grain for long lasting durability. Features: * Type 27 shape * Available with 5/8”-11 threaded hub * Non-woven synthetic fiber impregnated with abrasive grain * Three different grades What"s In the Box: * Mercer 397MRN 7 x 7/8-Inch Aluminum Oxide Prep Wheel