Cubic Millimeters
Cubic millimeters are volume units in the metric system. A cubic millimeter is a unit of volume equal to the volume of a cube with sides measuring one millimeter each. It is a very small unit of volume commonly used to measure tiny amounts of liquids or solids. For example, a single drop of water may have a volume of approximately 50 cubic millimeters.
US Liquid Barrels
A US liquid barrel is a volume unit used in the United States to measure the volume of liquids. One US liquid barrel is equivalent to 31.5 US gallons or about 119.24 liters.
To convert this unit please visit: US liquid barrel conversions.
Note that there are many types of barrel so be sure to choose the correct one for your needs.