For 80 years, Durham's Rock Hard Water Putty has been making repairs in wood, plaster, drywall, stone, tile, concrete and other stable surfaces. Just add water to this powdered material, apply it into voids, cracks and holes. When thoroughly dry, it can be sanded, drilled, sawed and painted. Repaired areas are very hard and long lasting. Durham's can also be cast or molded to reproduce missing trim pieces or in handicraft or artistic applications.