There is nothing worse than getting into your car as you prepare to leave for work and discovering your battery is dead. You could call AAA - if you have a membership, your parents - if they live close by, or a friend - if you have any of those. Regardless of whom you call, by the time they get there, you are going to be late to work.

The other option is to buy a portable battery pack that doubles as a car jump-starter and keep it in your trunk for just such occasions. There are a ton of different companies that make these things, and today, one of them is on sale.

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