O-Cel-O Stay Large Sponge contains a patented antimicrobial that helps the sponge resist bacterial odors, killing odor-causing germs and bacteria in the sponge. Sponge resists staining and crumbling from mildew and frequent use. Ideal for washing woodwork, cars, boats and household cleaning tasks. Highly absorbent, durable sponge is made of cellulose that is derived from wood pulp, a renewable resource.