Book smarts, beautifully applied. This Princeton® Collection bathtub is made of Americast®, our revolutionary alternative to cast iron that's more durable and lighter. Features a glossy porcelain finish, beveled headrest, lumbar support, slip-resistant surface and a factory-installed overflow drain. Above-floor rough alcove installation. Learn more about Americast. Americast® is our proprietary, revolutionary alternative to cast iron that's more durable, lighter and costs less to install. Thanks to inherent manufacturing advantages, Americast bathtubs can be made deeper, flatter and roomier than their cast iron counterparts.