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 glass present, the capacity line. There are no legally prescribed sizes for beer volumes, but the stated capacities, which are a legal requirement, must be formally tested by the hotelliers and breweries. In Canada, Federal law mandates a standard imperial pint. However, this law is rarely enforced, and establishments typically sell US pints or other measures as "pints." The Republic of Ireland uses the imperial 20 fl oz pint measure (≈568 ml), where legal metrology marks are used to show that a glass has passed inspection by the National Standards Authority of Ireland, a state-run body which enforces a number of