From the description: The strike cruisers of the VLEZHDATL class are typical Zhodani escort and frontier war ships. The highest technology available is used on these ships. VLEZHDATL class ships are usually found in groups of three, in a triangular formation. (...) Because of the Jump-1 limitation of the VLEZHDATL, special arrangements must be made for extended patrols. On such patrols an auxiliary tanker is assigned to the squadron. This unarmed, unarmored ship provides enough fuel for three ships to make another jump.