Miracle Sealants 511 Impregnator Penetrating Sealer forms an Invisible Barrier on Medium to Dense Porous Surfaces 511 Impregnator is specifically designed for the protection of all medium to dense porous surfaces. It forms an invisible barrier that is resistant to moisture and stains while allowing vapor to escape. It is not a surface coating and will not alter the natural look. All surfaces treated are harder and less slippery. Coverage: 500 - 4,000 square feet per gallon.