Anker PowerCore Jump Starter mini
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This is one of the best investments a car owner can make. For $80 you get a portable car starter that can fit in your pocket, better yet your glove box. Having a shit car, I have used mine 4-5 times now. Three times on a single charge and it was still at 50%.
The device is a small dual USB charge with adapter for jump starting cars. It is optimized for high current jump starting and will start even large trucks within 30 seconds. It can also charge an iPhone, iPad and has a flash light. It is super handy for camping as well as roadside jump starting.
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The device comes in a nice case with indoor and car charging cables. This is probably the most useful device I own, I got it for Christmas a few years ago from my mother. I really wanted one and threw it on my wish list. I've used it 5-6 times since then.
I've used it three times since the last charge about 4-5 months ago (while sitting in the freezing car all winter), and it is at 50% after a recent third jump.
A single jump and this thing pays for itself, I have AAA which my mother also got for me (thanks mom!) but that can take up to 2 hours to arrive. I can be up and running in less than 30 seconds, literally.
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Even if you have a nice new car unlike me, shit happens, an alternator goes, you leave the key in the ignition, you will always have a situation where you have to jump your car every few years. For the price of a nice steak dinner for two you can have the peace of mind when you are at your worst.
You can find them on Amazon for $80 with free shipping. This is a newer model than mine, and now I want a spare.
Remain safe on the roadside in any perceivability conditions with an intense crisis LED. Keep work or family advised of your whereabouts—2 USB ports with Anker's Power IQ rapid charging tech guarantee your telephone remains controlled on.