The Stak'at-class science vehicle was a scientific mobile base employed by the Klingon Empire. They were a gravitic sensor platform and could serve as a mobile laboratory. They had a crew of three who would sit at the nose of the vehicle where they would receive the sensor telemetry and other necessary information from the scans conducted.
They were unusual for Klingon forces in that they possessed no form of weaponry beyond its myriad of scientific tools which are apparent by the large ring shaped formation at the centre of the craft. This meant that it required a dedicated escort when travelling through hostile territory.
These vehicles were known to possess power shielding against sources of radiation making positions within these science craft a respected job within the Empire. This is simply because that radiation could leak into the craft and kill the crew.