The ship was shaped like a Star Destroyer, with a ridge going up to its bridge and had at least two thrusters. The hold could carry at least one TIE/LN starfighter, sharing room with additional cargo. The ship was simple enough to fly that it could be done by only one crewmember.
One such vessel carried a vital piece of the Death Star II's weapons systems in 3 ABY, when it was ambushed by Wolf Squadron. The crew were killed, and the ship was brought to the Rebel's base on Annamar. Darth Vader later led a successful mission to recover the craft and its valuable contents.