Sulfuric acid anodize, or Type 2, is the most popular anodizing solution, particularly for aluminum. It offers a broad range of finish thicknesses that are generally categorized as “moderate.” The sulfuric acid coating changes the properties of the substrate, increasing the metal’s wear and corrosion resistance, improving its ability to retain lubricants, and providing electrical and thermal insulation. On an aesthetic level, this type of anodizing also makes for great results when dying the metal with vibrant colors.