Felt wheels, because of their price, are the obvious Cadillacs of the polishing and buffing world. They are constructed of wool fibers compressed into wheels of varying hardness from extra soft to flint hard. Each of these densities or hardnesses has its place in polishing and finishing, but the most common are soft, medium and hard. Felt wheels can be used for every finishing operation, from set-up wheels with greaseless or glue based compounds to the final buffing with a coloring compound for a mirror finish. They are particularly well suited to operations where the operator wishes to polish to a grind or casting line without erasing the line. Soft cloth wheels roll over edges and cause washed-out or blurred lines.