Produced by the same manufacturer as the Trolac, the Kelrun is a heavy modification of that design. The Kelrun Priority Transport exchanges cargo capacity and weapons systems for both larger, more advanced commercial warp engines and stronger, more reliable shielding. These upgrades come at an extreme cost to ship system efficiency, however, and the Kelrun most notably suffers from power deficiencies caused by an overstrained reactor.

Kelruns are commonly found in both Cardassian and Bajoran service.