Mitsui Mining and Smelting Co Ltd (Mitsui Kinzoku) is a Japanese company which primarily supplies and produces metals for manufacturers of both automobiles and telecommunications devices. The company is split across four segments: Engineered Materials, within which Mitsui Kinzoku supplies catalytic converters, battery materials, and copper foil used in microelectronics; Metals, which involves mining, smelting, and recycling copper and zinc; Automotive Parts and Components, which principally manufactures door-related automotive parts; and Affiliates Coordination, which includes perlite, die-casting, and engineering projects. Whilst Mitsui Kinzoku derives the majority of revenue domestically, the company operates in several overseas markets, notably the United States and mainland Asia.