Beer, unless bottled, is sold simply by the glass, and the size of the glass can vary from outlet to outlet. Drink servings on the Continent are seldom standardised as in Britain and Ireland. Having enforced metric measures where they do not apply in Europe, the British government has failed to implement metrication in several areas where it does apply. In some cases, the British government has adopted different metric units to those in use on the Continent. The millimetre has been accepted for a vast range of uses in Britain that would be unheard of in other countries due to its tiny size.
Centimetres are much more common in Germany.
While the DTI has decreed compulsory metrication in Britain on the grounds that metric units are adopted all over the world for comparison and compatibility, a vast range of manufactured goods in Europe are based on non-metric specifications for the same reason. Car tyre diameters are specified in inches throughout Europe as are most sizes of bicycle tyre and wheel diameters. European manufacturers willingly produce goods designed to imperial specifications specifically for export to non-metric markets. Examples of this are Belgian carpets and rugs, and French glasses in pint and half-pint sizes. Although Britain's supporters of metrication regard Europe as a decimal role-model, there exists a wide range of other systems on the Continent which are based on customary divisions of twelve and sixteen.