The Jem'Hadar heavy escort carrier was a starship design developed by the Dominion following the end of the Dominion War. It was constructed in the Gamma Quadrant for use by the warrior Jem'Hadar with 350 serving as crewmen on-board these ships which were designed to work in line with the tactics employed by them. These vessels held a single hangar which often allowed them to support a wing of Jem'hadar fighter class starships. They in turn worked in conjunction with the Dominion Coordination Protocols that allowed them to be dispatched in specific deployments such as Fleet Maneuver Gamma. The presence of a heavy escort carrier on a battlefield was enough to swin the tide of battle in the favor of the Dominion. (STO website: Dominion Lock Box)