Comparison of the imperial and US customary measurement systems adopted a system based on the 231-cubic-inch wine gallon for all fluid purposes. This became the US fluid gallon. Both the imperial and US fluid gallon are divided into 4 quarts, 8 pints or 32 gills. However, whereas the US gill is divided into 4 US fluid ounces, the imperial gill is divided into 5 imperial fluid ounces. So whilst the imperial gallon, quart, pint and gill are about 20% larger than their US fluid measure counterparts, the fluid ounce is about 4% smaller. Note that one avoirdupois ounce of water has an approximate volume of one imperial fluid ounce
Pint measure in Canada, they are still 20% larger than the American ones. In the British and Irish metrication processes, the pint was replaced by metric units as the legally defined primary unit of measure for trading by volume or capacity, except for the sale of draught beer and cider, and milk in returnable containers. The pint can still be used in those countries as a supplementary unit in all circumstances. Legislation in the UK mandates the use of the pint as a measure for draught beer and cider (in pubs for instance). For milk, if returnable containers are used, the