Hi Zoltan, just a thought - a 12000mAh power pack may not start a large capacity car. Another member did some research on these @2 years ago and obtained a deal through a contact he had. I do not recall the capacity of the power packs he was recommending but they were of a much larger capacity than this (possibly @ 36000mAh or higher I think). Just before you go to order one just check it will do you for what you want... They are great devices but I'd hate to see you get one & it not work on your car.
Cheers