These features are neatly supplemented by a compact and robust build: The device is made from a safety-orange or gray plastic that's highly visible, water resistant, and floats, and it includes a nylon-webbing handle for carrying and hanging. Best of all, the whole package weighs less than a pound, making it a perfect companion for long trips.
K-Tor Pocket Socket 2
K-Tor's $65 Pocket Socket 2 (4 of 5 rating) is unique among all the hand-turbine chargers here in that it eschews USB ports in favor of a standard 120V power outlet.
The Pocket Socket 2 is also the most comfortable of all the generators I've tried, thanks to a wide (7 by 2.3 by 2.3 inches) body that weighs less than a pound and offers a firm grip, along with a crank that requires very little effort to operate after the first couple turns. The device's design is such that you can use both arms in a large, sweeping motion to power the turbine, making it easier to crank for extended periods of time (particularly if you can work in tandem with a friend).
The Pocket Socket 2's outlet is rated at 10W, which is enough to handle even a tablet's USB charger. Of course, the downside to the AC-outlet approach is that you must keep that charger on hand, with the generator, if you want to power your electronics. Still, having a proper 120V outlet also means that you can power non-standard devices as well, regardless of what cockamamie connectors they may use.
However, the Pocket Socket 2 does not include a built-in battery, presumably because such a battery would need to be impractically large in order to be able to provide 120 volts. As a result, this device won't provide your gadgets with an immediate battery boost, which may diminish the Pocket Socket 2's usefulness in an "I must make a call right now!" emergency.
MyFC's €199 PowerTrekk (4 out of 5 rating) is not priced for the budget conscious, but it's unique among the products I tested in that it works just about anywhere, at any time of day or night, as long as you have a couple essential substances on hand.
The PowerTrekk contains a 1500-mAh rechargeable battery that offers enough juice to charge your iPhone once, with a little power left over for, say, running a USB flashlight. The 5-watt USB-power output is not quite powerful enough to recharge a full-size iPad that's in use, but it should be able to keep the iPad's battery from discharging further for as long as the PowerTrekk's own battery lasts.
You can charge the PowerTrekk's internal battery using a standard USB charger, but the PowerTrekk's innovative feature is that it can use special fuel cells that, when combined with water, generate electricity. Each single-use fuel-cell puck produces enough electricity to give a current iPhone about half of a full charge, even if you're hundreds of miles away from the nearest outlet.
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