The private-class ship is one of the 7 different types of derelict ships in the game. These ships generally only have one airlock door, and only one generator which powers the whole ship (This ship can be especially tricky to handle if you don't own remote power and the ship is infested with slime, as the slime will eventually reach the only generator). In a class-A private vessel, there are roughly 10 medium-large sized rooms.

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The generator on a Private A derelict ship