SD Etching, or Standard Definition Etching, involves a chemical process where designs are etched onto the surface of the metal plate. This technique results in shallower engravings, giving the belt a flatter appearance. While SD Etched belts are often more affordable, they may lack the depth and detail found in their HD Engraved counterpart. However, they still offer a clean and polished look, making them a popular choice for casual collector.