CMS Spanner was a Shearwater-class frigate, built for the Caspian Navy. She had been newly built, and had just completed her star trials in 8 ABY when the Imperial War of Aggression began. Trials were conducted under the command of a Captain Sodehl, a Casohavi Sarian, and while the ship was probably going to be handed off to another captain for deployment, he took command of Spanner when hostilities erupted. Spanner was named for the prominent city of the Casohavi on Mergansar.