It has the beauty of porcelain with strength of cast iron yet lighter weight. The insulated construction absorbs waste disposal noise and resists stain, rust, oxidation, chipping, and scratches. The surface can be polished with ordinary liquid sink, countertop, or auto polish to maintain beauty and luster. It is versatility designed undermount installation. Mounting clips required for installation (not included). All Thermocast brand Cast-acrylic sinks are certified by the National Association of Home Builders Research Center and carry a Lifetime Warranty.