The Rubi Hidro Pro Plastic float is ideal for cleaning all types of surfaces, particularly for the cleaning professional ceramic tile installers have to do after installation, such as grouting. The high-absorption HIDRO sponge is made of flexible polyurethane with a polyester base. Its high degree of absorption and resistance to abrasion make it the ideal sponge for cleaning all types of surfaces, especially the roughest ones. It is not recommended for use with acid-based products. Specifications: Sponge Size: 28 x 14 x 3cm. Absorption Level (1-4): 3. Resistance to Abrasion (1-4): 3.