The pucks, which weigh roughly 1.5 ounces each, are easy to operate — just pour water into the PowerTrekk, insert a puck, and seal the device — and they can even be taken on an airplane. Except for a slight hiss when you first insert a new puck in the device, the PowerTrekk is silent while running, and it doesn't emit any significant fumes or odors that I could detect.
My only nitpick with the PowerTrekk is that although the device's 8.5-ounce weight and compact (2.6 by 5 by 1.7 inches) body make it good for trips, its battery is quite a bit smaller than those of the other products here, and you don't get much juice from a single fuel cell. A larger battery would be great for extended trips in the wilderness — the pucks aren't heavy or bulky, but you can stuff only so many things in a backpack, so a higher initial reservoir of power would save space overall, even if it ended up making the PowerTrekk itself bulkier and a bit more expensive.
Still, if you can get over the price of the pucks — roughly €5 to €6 each, depending on the quantity you buy — the PowerTrekk is a unique option. It's the only charger I tested that you can pull out after an extended period in storage and use in complete darkness without any physical effort.
Power Practical PowerPot V
Modern camping accessories never cease to amaze me. Tools that were heavy and humdrum when my dad and I used to go into the wilderness as a kid have turned into compact, lightweight technological wonders — in the space of barely twenty years.
Power Practical's $150 PowerPot V (4 of 5 rating) is a perfect example. It is, as its name implies, a cooking pot — made of hard-anodized aluminium — that incorporates a thermoelectric charger. All you need is water (or, say, soup) and a source of heat, and as long as both those resources are available, the pot will provide enough electricity to power a smartphone or other USB device. (The PowerPot doesn't include a battery — like the Pocket Socket 2, it provides power only while in active use.)
The PowerPot's actual pot can hold one quart of liquid and weighs a mere 12 ounces when empty. It comes with a lid that doubles as a skillet or bowl, and a heavy-duty charging cable that resists heat and provides a standard USB port for connecting your device to be charged. An adapter that provides Mini-USB, Micro-USB, and 30-pin Dock connectors is also included, as well as a carrying bag and what is probably the cutest USB light I've ever seen. (The company says that a Lightning-connector version of the adapter will be available later in 2014; in the meantime, you can use any USB-to-Lightning-connector cable, such as the rugged Syncable I mentioned above.)
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