Below is a list of Custom Anodizing manufacturers from Elgin, Illinois. Custom anodizing is a process in which a small number of parts are uniquely anodized in order to achieve application-specific characteristics, such as the level of hardness or a desired color. The reason it is typically done with a small number of parts is because it is so specifically-geared to one application, and not designed as a mass production open to a wide range of applications.