A grav-tank was an armored vehicle propelled by an anti-gravity engine. In 2328, on day zero of the Occupation of Bajor, Gar Osen observed three Cardassian grav-tanks approaching the Naghai Keep in the city of Korto. They resembled legless beetles with pintle-mounted disruptors. (TLE - Terok Nor novel: Day of the Vipers)