Big Deals via eBay offers the open-box Motorola 2,000mAh Universal Dual-Charging USB Portable Battery Pack 2-Pack in Black/Red or White, model no. P2000, for $9.99 with free shipping. That's $12 under the lowest total price we could find for the quantity elsewhere. Each power pack can charge up to two devices simultaneously via the built-in micro-USB cable or standard USB charging port.
No warranty information is provided.