The spiral wave disruptor was the main energy weapon on Cardassian Union starships during the 24th century. Similar to the disruptors used by the Klingons and Romulans the method of transferring energy to the weapon is different. This results in a disruptor that is more phaser-like. (Ship Recognition Manual, Volume 2: Starships of the Cardassian Union)
Many Cardassian ship designs feature a large spiral wave disruptor mounted at the aft of the vessel.