<P> A drum is a cylindrical container used for shipping bulk cargo . Drums can be made of steel, dense paperboard (commonly called a fiber drum), or plastics, and are generally used for the transportation and storage of liquids and powders . Drums are often certified for shipment of dangerous goods . Shipped goods must be matched with the make of drum necessary to comply with applicable regulations . Drums are also called barrels in common usage . </P> <P> It is common to hear a drum referred to as a barrel and the two terms are used nearly interchangeably . Many drums have a common nominal volume of 208 litres (55 US gal; 46 imp gal) and nominally measure just under 880 millimetres (35 in) tall with a diameter just under 610 millimetres (24 in) and differ by holding about thirteen gallons more than a barrel of crude oil . In the United States, 25 - US - gallon (95 l; 21 imp gal) drums are also in common use and have the same height . This allows easy stacking of mixed pallets . Barrels can be constructed of plastic, laminated paperboard or steel . </P>

What is the diameter of a plastic 55 gallon drum