The Mercer 397GRY is a 7 x 7/8-Inch Silicon Carbide Prep Wheel. This Mercer Prep Wheel can be used with any 7/8-Inch arbor grinder. Features: * Type 27 shape * Available with 5/8-Inch-11 threaded hub * Non-woven synthetic fiber impregnated with abrasive grain * Three different grades What"s In the Box: * Mercer 396HGRY 4-1/2-Inch Silicon Carbide Prep Wheel