The Jupitris-Class was one of the first ships ever built by the Kadian Humans, and to date the largest. These ships were built by the hundreds to facilitate a constant flow of mined Helium-3 from Gas Giants as well as other minerals. They are so well engineered that its never crossed any ones mind to design a replacement. During the invasion these ships were nearly wiped out by the CIS forces, killing thousands of civilians. While they didn't participate in any battles, besides the CIS just out right destroying them, three Captains against all odds managed to get their ships safely to the defense fleet, giving them the fuel and materials need to help win the war.