Convert from milliliter to drum [metric, petroleum]

Unit Definition (milliliter)
The milliliter is a very common metric unit of volume. One milliliter equals 0.001 liter, exactly one cubic centimeter (cm³ or cc), or approximately 0.061 023 7 cubic inch or 16.231 U.S. minims. The milliliter is used almost entirely for measuring the volumes of liquids, with solids being measured in cubic centimeters.

Unit Definition (drum [metric, petroleum])
The drum [metric, petroleum] is a unit of volume sometimes used in the oil trade. In the metric world, drums of 200 liters, 205 liters, and 208 liters are in use as substitutes for the traditional size.