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. INDEPENDENT LABORATORY TESTS SHOW TILE, STONE & GROUT SEALER OUTPERFORMS COMPETITIVE PRODUCTS. (Test results are available upon request).