Pro Art - Combo Set Silk Wool Grass Sponges - Pliable natural sponges can be used for watercolor washes, soaking and stretching papers and are excellent for pottery making. Finely grained and highly absorbent. Use with acrylics, oil, watercolors and fabric paints. Ideal for sponge painting, faux finishes, stippling and staining. This set comes with a variety of sizes and textures of natural sponges.