Silicone carbide impregnated in nylon bristles is self-replenishing as brush wears, offering unmatched value that outlast floor pad over 100 to 1! That translates directly into time and cost savings. Featuring our water and chemical resistant Tuff-Block® to insure that the block last as long as the bristles for maximum life expectancy. Must be run in a wet environment. An aggressive brush for general scrubbing or stripping finishes from hard surfaces. Effectively cleans wide grout lines. Grit Size: 80. Bristle Color: Black; Bristle Diameter: .050. Pad Replacement: Black.