IKS Bortas (D5 class)

The IKS Bortas was a Klingon D5 class battle cruiser in service to the Imperial Klingon Defense Force in the 22nd century. She was under the command of Captain Duras. 

The Bortas engaged the Enterprise in 2152 when the latter ship rendered aid to a refuge ship. (This refuge ship was transporting fugitives from a planet the Klingons had recently annexed.) Enterprise successfully escaped the battle cruiser by blinding their sensors with a carefully placed shot into a gas giant's rings, thus concealing the retreat of the Terran ship.