Liquid Cargo Carriers, or tankers, are specifically designed to transport liquid cargoes in bulk. Although tankers differ greatly in size, their cargo handling equipment is similar. Specific features of the cargo handling equipment differ, however, based on the intended cargo. These differences may limit the capability of the ship to carry cargo other than that for which it was designed. Tanker capacities are stated in terms of cargo deadweight (DWT) or barrels (BBL). DWT is measured in LT of 2,240 pounds and 1 BBL equals 42 US gallons. The parameters that define a militarily useful tanker are the capability of carrying POL, a capacity within the range of 2,000 to 100,000 DWT, and a sustained speed in excess of 12 knots