As part of their technology trade with the Klingons, the Romulans procured the plans to the Klingon D7 Cruiser. The Romulan implementation of the hull was classified as D7-A. The first example of the ship-type to be equipped with a working cloaking device, the Romulan's D7-A was otherwise little different than its Klingon counterpart. The one point of interest is the replacement of the heavy photon torpedo with a plasma mortar, the precursor to the plasma torpedo.