Chromic Acid Anodizing is an electrochemical process that creates a thin aluminum oxide film by rapidly controlling the oxidation of an aluminum surface. The resulting aluminum oxide film is electrically non- conductive. The active ingredient in Type I Anodizing is chromic acid. Type I anodizing produces a thinner film than Type II and Type III Anodizing (hard coat) and produces enhanced drawing and forming characteristics. Chromic acid anodizing is used for flight-critical aluminum components that are subjected to high stresses, such as landing gear. Type I Chromic Acid Anodizing works best on aluminum with few alloying elements.