Vacuum formed ceramic fiber skimmers are used for removing slag, dross, and impurities in metal from furnaces and ladles . Our vacuum formed ceramic fiber skimmers are 7.5 inches in diameter. Our slag skimmers are ideal for removing contaminants from all types of metals. These are rigidized for extra strength – no cheap fillers, no resin binders, do not emit harmful pollutants, and do not contaminate the metal.