Expertbattery via eBay offers a 10,400mAh Power Bank Battery Pack in Black for $15.50 with free shipping. That's $4 under our January mention and $17 below the lowest total price we could find for a similar battery pack elsewhere. It features 1A and 2A dual USB output and a built-in microUSB cable. It works with iPod, iPhone, smartphones, digital cameras, and other devices.
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