In most countries, the basic wine bottle size is 75 cl (also labelled as 750 ml). Wine bottles have been used for centuries, but standardization of sizes is a relatively new phenomenon. When all bottles were hand-blown, size inevitably varied; with the advent of machine-made bottles, it became possible to reproduce exact sizes, but only in the 1970s did the European Union (EU) start to enforce standardization within its member countries. Non-member countries gradually fell into line for the sake of convenience. Many regions have their own traditional bottle sizes, though most are multiples of the standard bottle size.