The document discusses the materials used in manufacturing aerosol containers. It describes the different types of containers - tinplate steel, aluminum, stainless steel, and glass. Tinplate steel containers are the most commonly used type and are made by electroplating tin on steel sheets that are cut and assembled. Aluminum containers provide greater corrosion resistance but can be corroded by pure water and ethanol. Stainless steel containers are very strong but limited to smaller sizes. Glass containers are used for some pharmaceutical aerosols. The document also discusses valve assemblies and the inert materials like plastic, rubber, aluminum, and stainless steel that are approved for use.