An ' ship is an oil tanker smaller than and with a breadth above 32.31 m. The term is based on the Average Freight Rate Assessment tanker rate system. class tankers are largely used in the basins of the Black Sea

Black Sea

The Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...

, the North Sea

North Sea

In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...

, the Caribbean Sea

Caribbean Sea

The Caribbean Sea is a sea of the Atlantic Ocean located in the tropics of the Western hemisphere. It is bounded by Mexico and Central America to the west and southwest, to the north by the Greater Antilles, and to the east by the Lesser Antilles....

, the China Sea

China Sea

The China Seas consist of the seas of the Western Pacific Ocean, around China:* Bohai Sea* Yellow Sea* East China Sea* South China SeaOther uses*China Seas , a 1935 American adventure film...

and the Mediterranean. Non-OPEC

OPEC

OPEC is an intergovernmental organization of twelve developing countries made up of Algeria, Angola, Ecuador, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, the United Arab Emirates, and Venezuela. OPEC has maintained its headquarters in Vienna since 1965, and hosts regular meetings...

 exporting countries may require the use of tankers because the harbors and canals through which these countries export their oil are too small to accommodate very-large crude carriers and ultra-large crude carriers .