Rover 2 was the rover that Mark Watney used.
It was modified significantly to fit the oxygenator, the water making machine and all his food. He drilled holes into the top and put a 'balloon' in it in order to make the right conditions for the oxygenator and to make it bigger. Watney also salvaged the power cells from the abandoned Rover 1 to double the power lifespan of the Rover 2. On top of all this he also dug up the RTG to use for heat as the Rover heater used up a quarter of the power, in doing so he actually made it too hot and so he had to strip back some of the insulation.
