The Interdictor-class Star Destroyer was a variant of the Imperial I-class Star Destroyer equipped with gravity well projectors.
Sienar Fleet Systems already produced an Interdictor, the Immobilizer 418 cruiser based on a 600 m Vindicator-class heavy cruiser (also used for the Enforcer-class picket cruiser). Though it was decently armed for its size, it was a high priority vessel that was generally unable to hold its own in combat, especially if the battle involved Imperial Star Destroyers and comparable vessels.
Kuat Drive Yards decided to produce their own Interdictor offering to rival that of SFS by using an Imperial I-class Star Destroyer hull as a base. To make room for the gravity well projectors, half of the turbolasers and ion cannons, as well as eight of the Phylon Q7 tractor beam projectors found on the original Imperial-class Star Destroyer, had to be removed. The Interdictor-class Star Destroyer's reduced hangar held four squadrons of TIE fighters. As such the Interdictor did not make an excellent combat destroyer.
The Interdictor-class Star Destroyer did not require additional support when performing patrol and customs duties. Some bold commanders such as Loka Hask even used the ship to pull armed convoys out of hyperspace and destroy them.
Nonetheless, like the Immobilizer, the gravity wells remained a major drain on the ship's main reactor. This had the potential to compromise defenses in heavy combat. For instance, while Loka Hask's Dominator had interdicted and was destroying a New Republic Convoy, Rogue Squadron's X-wings counter-attacked by hitting Dominator with a salvo of proton torpedoes. While an Imperial Star Destroyer's shields would have easily held up against such an assault, Dominator's shields partially collapsed and the hull took some damage, prompting its commanders to call off the battle. (Rogue Squadron also successfully used this tactic on the Immobilizer 418 cruiser Aggregator which caused it to retreat.)