Tile Grout Sponge Large 22 pieces. These fine pore hydro sponges are made in the USA Our tile grout sponge is the densest sponge on the market, domestic or import. Our quality tile grout sponges have all the advantages of the best natural sponges and last longer. Size 6.5" x 4.5" x 2.2". Read Bulk Tile Grout Sponges Shipping and Storage Information.