I wouldn't buy one that plugs into a lighter. The lighter wiring on 240s is
pretty puny, and any oxidation in the socket will make it not work
effectively, that and you're also running through those failure prone fuses
and fuse panel. The jumper cable type is far more effective and versatile
since it connects directly to the battery. I once used one to bring home a
car with a dead battery and alternator by setting the whole jump starter
under the hood to keep the ignition powered up.
