Flextile 49 Silicone Sealer is a low viscosity, penetrating sealer that reduces water absorption of grout or masonry surfaces on which it is applied and helps to preserve the appearance of these surfaces by reducing staining, soiling and efflorescence. Recommended for sealing the surface of all unglazed ceramic floor tiles and for sealing Portland cement - based grouts. Also recommended for use on above grade surfaces of brick, sandstone, stucco, concrete block or concrete.