Unitized Wheel, Abrasive Material Silicon Carbide, Density Rating Hard (7), Grade Medium, Series CP-UW, Face Width 1/4 in, Maximum Operating Speed 12,100 RPM, Overall Diameter 4 in, Connector Size 1/4 in, Connector Type Unthreaded Hole, Quick Change System Not Applicable, Abrasive Type Non-Woven, Color Gray, Resistance Properties Load, Package Quantity 20