The first rule of thermodynamics states that energy can neither be created nor destroyed, only converted from one form to another. So when this Etón BoostTurbine portable battery charger with built-in hand crank charges your devices for free, what it's really doing is turning a little sweat and elbow grease into precious electricity.
Sure, one minute of cranking will only get you about 30 seconds of talk time, but if you're stranded on a desert island or desperate to order some pizza before your phone dies, then turning a handle is a small price to pay, don't you think?
Lazy gadgeteers will be relieved to hear that you can also juice up the charger from a standard plug socket for crank-free charging, with the BoostTurbine2000 model offering up to a full charge in comparison to the BoosTurbine1000 which has enough juice for a 50 percent charge.
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