This is a highly portable (1 lb, sized 6-1/2 x 3 x 1-1/4") rare-earth emergency car starter that will deliver at least 200 amps (max 400) to a depleted car battery in an emergency. Rating is 12,000 mAh (Milliamp Hours). And it will do it multiple times if adequately charged. It should be "topped up" every 3 months even if not used. And the included 12 V plug allows you to do this "on board", so you never have to take the device away.
In addition, the battery has 2 USB ports and can be used to charge a full variety of cell phones, MP3 players, iPads, and tablet computers using the bundle of connectors (shown).