RS500 was developed for protecting and weatherproofing extremely porous stone (limestone, sandstone, moss rock), concrete, masonry, stucco, cast stone, mortar grout joints, plaster and other very porous substrates. Ultra Porous prevents saltwater erosion, resists water based stains, and weatherproofs and protects. RS500 will also enhance and bring out the colors in most stone curing with a natural matte finish. Although designed for extremely porous substrates it is often used on denser materials/stone to achieve enhancing color effects. An Ultra Porous RS500 treated surface will inhibit and resist penetration for the life of the matrix. Because the matrix is a union of RS500 and the material it becomes part of the material and will not separate or tear from the surface.