eCase via Amazon offers the Kmashi 10,000mAh Dual-USB External Portable Battery Pack in Black, model no. 6.96E+12, for $13.99. Coupon code "K65O9FTS" cuts that to $9.20. Plus, Prime members bag free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $6.52.) That's the lowest total price we could find by $7. It features two USB ports, intelligent power management, and overcharge and short circuit protection. Deal ends October 31.