From Halopedia, the Halo wiki
A war-freighter is a class of ship that was used by the Covenant. The Covenant was known to use war-freighters as tithe ships in its tithe fleets. Some models still in use are quite old. War-freighters are dwarfed in size by CPV-class heavy destroyers but are still heavily armed with a plasma cannon and two side-mounted turrets. Following the end of the Human-Covenant War, the Sangheili commander in Jul 'Mdama's Covenant, Gek 'Lhar, commanded a war-freighter during his time spent salvaging and pillaging.
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