After experiencing the frustration of a sudden flat battery during Winter and the need to find someone who will jump start me, for peace of mind I have purchased a Suaoki 12V 800mAh Booster starter. The quality is good. Well priced. Easy to use and suitable for a 2lt Engine. Will also charge a mobile phone and has an emergency led light. However for a larger capacity engine or a diesel you will need a bigger model.
I bought this to run some 12v lights, it has done this very well but the true power of the jump starter showed itself when my 4.2ltr six cylinder 4wd wouldn't start off the battery. This little pack started it twice and still had a full capacity shown by the units test lights. Love it! Bought 2 more!