100% Cork from Portugal High Density and Quality bulletin board quality/Dart board backing Cork sheets are perfect for floor and underlay, coasters, crafting, gaskets, and other custom designs. As a lower cost alternative to felts and foams, cork is a perfect natural sound and moister barrier used in construction and design. We offer both a standard underlayment quality cork as well as a higher grade quality for gaskets and more technical uses. These sheets are all A Grade made in Portugal Cork.