UK Barrels
A UK barrel is 36 imperial gallons (not to be confused with American gallons), about 163.659 liters or 0.163659 cubic meters. It is based on the traditional wine barrel used in the United Kingdom.
US dry gallons
A US dry gallon is a unit of volume measurement normally used for dry goods such as grains, fruits, and vegetables. It is about 4.40488 liters or 0.16 cubic feet.
Note: The US dry gallon is different from the US liquid gallon, which is used for measuring liquids and is slightly smaller in volume.