Octuple barbette heavy ion cannon

The octuple barbette heavy ion cannon was rarer, more expensive version of the Octuple barbette heavy turbolaser, which was mounted on Imperial II and Imperial III-class star destroyers, as well as on the Arrestor II-class star dreadnought.

History
Developed by Endor Heavy Weapons, a subsidiary of Endor Drive Yards, the first prototype was built in 6 BBY, but didn't start entering production until 3 BBY. These weapons used the same targeting systems and sensors as its turbolaser counterpart, and when used in conjunction with the heavy turbolaser model, it proved to be a deadly combination as these heavy ion cannons could disable shields of the Venator-class in only 10 minutes.

By 11 ABY, these guns were considered obsolete, but historians and experts agreed that these heavy ion cannons were some of the best of its type.