CounterArt Water Birds Mallard Absorbent Coasters, Set of 4 Set of 4 absorbent coasters with attractive design combines artistic form with high function Coasters are natural stoneware with decorative transfer print Each coaster has a durable cork backing to protect countertops and furniture; measure 4 inches across To remove stains, soak coaster in 1 part household bleach and 3 parts water until stain lifts, then rinse and air dry Holders available; look for counterpart coaster holds ( sold separately)