Tile, Stone & Grout Sealer penetrates into the pores of the surface to form a barrier that is resistant to moisture and stains while allowing complete vapor transmission. Tile, Stone & Grout Sealer is an entry-level low-cost alternative to impregnating/penetrating sealers. It is not a surface coating and will not alter the natural look. All surfaces treated are harder and less slippery. It can be used on both interior and exterior applications.