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In page Customs union:

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A customs union was established by Switzerland and Liechtenstein in 1924, by Belgium, the Netherlands, and Luxembourg in 1948, by the countries of the European Economic Community in 1958, and by the Economic Community of Central African States in 1964.[citation needed] At that time, the European Free Trade Association was separate from the European Economic Community Customs Union.[citation needed] Free trade within the former was limited to industrial products, and no uniform tariffs were imposed on countries outside the Union.[2][3]