The Pakistan Steel Mills Corporation, colloquially referred to as Pak Steels, is a Pakistan-based company that produces long-rolled steel and heavy metal products in the country. Headquartered in Karachi, Sindh, the PSMC is currently the largest industrial mega-corporation in Pakistan, having a production capacity of 1.1–5.0 million tonnes of steel and iron foundries. Built with extensive contributions from the Soviet Union in the 1970s, it is among the largest industrial mega-corporation complexes, vastly expanded in an enormous dimension with construction inputs involving the use of 1.29 million cubic meters of concrete and 5.70 million cubic meters of earthworks, as well as containing approximately 330,000 tonnes of heavy machinery, steel structures and electrical equipment.