Teflon Surface Protector was recently added to Custom Building Products’ SurfaceGard Penetrating Sealer. SurfaceGard is designed to penetrate deeply into any tile or natural stone surface to protect it from oil- and water-based stains. The product provides protection for marble, limestone and granite, clay and Saltillo pavers, concrete, unglazed tile, grout, brick and masonry without altering the surface appearance, the company says. SurfaceGard is guaranteed for 20 years.