Antares shipyard scored a coup by recieving this special order from the Tholian Assembly. The Holdfast had been importing Federation freighters for use as Web Tenders. These freighters, filled with fusion generators, would feed energy into the spatial distortion effect the Tholians can create, known colloquially as "web". These ships are tactically limited to defense; their low speed (even with more powerful engines, the space frame cannot take the stress much above warp 3) limiting them to aiding the defense of fixed positions, so the Federation Defense Council maintains a stand of no objection to this transfer.
Tholians had been taking standard freighters produced by various shipyards when Atares introduced this new model with cosmetic similarities to the Tholian Patrol Corvette and locked up this small but prestigious market. Antares production capacity exceeds the Tholian need, so this class is also used by Starfleet and private concerns as a freighter and Antares has even released a variation for passenger transport.