Gallon Gallon The gallon () is a unit of measurement for volume and fluid capacity in both the US customary units and the British imperial systems of measurement. Three significantly different sizes are in current use: the imperial gallon defined as litres (4 imperial quarts or 8 imperial pints), which is used in the United Kingdom, Canada, and some Caribbean nations; the US gallon defined as 231 cubic inches (4 US liquid quarts or 8 US liquid pints) or about , which is used in the US and some Latin American and Caribbean countries; and the least-used US dry gallon defined
Keg UK and Ireland is quite different, whilst the couplers for kegs have been largely standardised to sankey, grundy and interbrew, a couple of others exist such as UEC and U-Type; however these are much less common. The kegs themselves are made from stainless steel or aluminium. The standard keg size is 11 imperial gallons (50 litre/88 imperial pints approx) and the vast majority of keg beers are supplied in this keg size. There are also smaller 30 liters (52.76 imperial pints) kegs usually reserved for more specialist and/or premium European beers. A number of manufacturers also produce 18 imperial gallon