A bacta tank was a cylindrical tank into which a being could be submerged for extensive exposure to bacta, a fluid that could accelerate healing and treat major injuries. Bacta tanks already existed during the Clone Wars, when the Galactic Republic used them to treat its injured soldiers. After being attacked and severely injured by a wampa ice creature on the frigid planet of Hoth, Commander Luke Skywalker was put into a bacta tank so he could recover from his wounds.

A bacta tank was located in Darth Vader’s castle on Mustafar, where the Dark Lord would relax and meditate outside of his life support armor with a modicum of comfort.