Tsakos Energy Navigation Limited is a provider of international seaborne crude oil and petroleum product transportation services. As of April 8, 2015, the Company operated a fleet of 47 modern crude oil and petroleum product tankers that provide marine transportation services for national and other independent oil companies and refiners under long, medium and short-term charters. The Company's fleet also includes one liquefied natural gas (LNG) carrier and two shuttle suezmax tankers with dynamic positioning technology (DP2), as well as VLCC, aframax, panamax, handysize, handymax tankers, and the two DP2 shuttle tankers. Its fleet is managed by Tsakos Energy Management Limited (Tsakos Energy Management). Tsakos Energy Management provides the Company with advisory, financial, accounting and administrative services. Its tanker fleet's technical management, including crewing, maintenance and repair, and voyage operations, is subcontracted to Tsakos Columbia Shipmanagement (TCM).