Cast iron can't keep up. Americast® is our revolutionary alternative to cast iron that's more durable, lighter and costs less to install. This traditionally styled, integral-apron bathtub features a beveled headrest, lumbar support and a StanSure slip-resistant surface. 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.