Goods may be manufactured in an FTZ except when specifically limited by law. Products may then be exported or sent into U.S. Customs territory. When products enter Customs territory, they are subject to Customs duties; if they are shipped to foreign countries, they are not. All new manufacturing operations are subject to the approval of the Foreign-Trade Zones Board and the District Director of Customs. Machinery or supplies of foreign origin used in the manufacturing process are subject to duty when admitted to an FTZ. In the particular case of imported textiles subject to quota, manufacturing is permitted only if the finished products are exported.