Interdictor-class star destroyer

Indterdictor-class star destroyers are are special kind of star destroyer that can generate a gravity well field, which makes it impossible to jump to hyperspace if you are inside of one. They are sent to a lot of major battles to keep enemy ships from jumping away. A trick they are sometimes used for is that if an enemy ships is coming toward them at lightspeed, they can turn on the gravity well to pull them out.