A sign created by placing a rubber stencil over letters and images and etching the background with a high-pressure mix of sand and air. The lettering and design areas are then sanded smooth and painted. Both wood and High Density Urethane or HDU, (a substitute that weathers better than natural wood), can be sandblasted, with HDU sandblasted signs usually resembling a stucco or sandy texture. It's easier to do fine detailed painting on sandblasted signs than it is on routed or carved signs as with sandblasted signs the design areas are raised, not recessed.