Grout construction sponge, polyurethane, combined. The sponge is universal and designed for washing various surfaces, including any type of tile, natural stone and glass mosaic. It has a two-layer structure: a hard layer of reticulated foam rubber is used for primary cleaning, and a soft - layer is used for surface finishing and water removal. The two-layer structure allows for rough cleaning and washing much faster; the highest quality polyurethane hydro sponge absorbs and releases water perfectly.